air conditioning repair

Hermetic compressor

2012-08-14T07:07:00.004-07:00

Hermetic compressor occurs:

1 - as a steel casing consisting of two parts welded electrically to one another and a cylindrical shape.
2 - 2 so that envelope suction pipe, one for the vapors sucked up, the other for filling refrigerant) and a discharge pipe are welded to the envelope.
3 - fixing lugs are welded to the envelope, on which are also located the terminals of the electric motor of the compressor.

role:
its role is to inhale the vapor produced by the evaporation of the refrigerant in
the evaporator has a low pressure, and discharging at a high pressure vapor such
compressed in the condenser.

Principle of operation:

Compressor operation involves two basic steps: the suction and discharge.

Aspiration:

When the engine is in operation, the rotor rotates and drives a crankshaft which allows the piston to descend in the cylinder by means of the connecting rod. During this phase, the valve 2 opens to the entrance of the refrigerant from the refrigerant circuit of the appliance (gas) in the room.

Refoulement:

After entering the refrigerant gas, the piston continued his run and compresses the room. the valve 2 closes tightly. Under pressure the valve 1 can then be opened and exhausting the fluid from directly in the refrigerant circuit of the device. The cycle can then resume

During step 1.

Exploded view of a compressor:

legend:

1 - Cylinder (Power Metal)
2 - suction guide (Oriente gas to the chamber of the cylinder)
3 - Head (Seals between cylinder and valves)
4 - valves (Allow the suction and discharge)
5 - Silent (attenuate the hiss of the gas during the discharge phase)
6 - Cover silent (Provides seal between the muffler and outlet hose)
7 - Pressure hose (Seals of refoulement to the refrigerant circuit)
8 - Counterweight (equilibrium rotational force of the crankshaft)
9 - Piston (Assure gas compression)
10 - Rod (Provides an intermediary between piston and crankshaft)
11 - Crankshaft (Used skewed transmission between rotor and piston)
12 - Rotor (Creates the rotational energy)
13 - Stator (Creates the magnetic field)
14 - spring suspension (balance and stabilize the engine in the bell)
15 - Connection motor (Provides input current in the motor)
16 - Starting system (here CTP)
17 - Oil Pump (lubricates the mechanical mounting)

Compressor start:
We can distinguish two variants starting aid:

Start relay:
Here is shown in series with the main winding (or "walk") ready to order a relay contact for the supply of the auxiliary winding (or so-called "boot"). When switched on, the electric current required by the main winding is very important. From this fact, the relay (energized) can order contact, feeding the auxiliary winding (start). The engine can then run the current decline in the main winding and therefore the relay (de-energized). Contact will open (off power to the auxiliary winding) and the engine will continue to run on its launched through the main winding. This system is no longer used in modern appliances.

Start by CTP:

This kind of startup is now current on all compressors powering next-generation devices. The CTP is a body whose electrical resistance (ability to curb the current) increases when the temperature increases. A power primary windings (walking) and auxiliary (start) are supplied. The motor can jump. As for the start relay, once started, the auxiliary winding must be cut. This is the CTP will do it. With the current passing through it, it produces heat and, consequently, an increase in its resistance to the complete blockage of the flow of current. The engine is started and fueled the running winding.

Note:

These two starting systems are not interchangeable because they require a clean manufacturing of the compressor motor. On engines start relay, the auxiliary winding is equal to approximately twice the value of the main winding. On starting motors PTC, the values of the two coils are substantially identical.

Thermal safety:

On the schematic above, we can see in series with the motor windings, thermal overload protection. It aims to protect the motor against overheating in case of malfunction. It consists of a bimetallic (alloy of two metals bonded in the form of a disc) which has the particularity to deform under the action of heat. Thus, when the engine overheats, the system cuts power. Similarly, if the engine power at startup, the electric current increases, the bimetallic strip heats up, deform, cut and de facto power.

What symptoms and diagnosis in case of failure?

Not cold in the refrigerator:

Winding-cut: Measure with an ohmmeter

Valve-HS: test compression and suction motor (proper equipment needed)
-Mechanical Problem.
Compressor "click" Thermal safety locks (overheating, boot problem, blocking mechanical problem in the cooling circuit)

Installing air conditioning

2012-07-31T10:01:00.001-07:00

Theair conditioning installation is not in itself a very complicated, but it must first acquire the equipment and to do, have correctly identified the needs they must meet.

Before installing air conditioning, several criteria are taken into account

-The volume to be equipped. Theair conditioning installation Does it concern a part or the entire housing ?
-The use of air conditioners or she will be more intensive or occasional ?
-What is the orientation of the parts to cool or heat ? What is their isolation ?
-What price do not exceed air conditioning did you set ?

This assessment will help you acquire this type of air conditioner rather than another.

To map, there are usually 2 types of air conditioners : mobile air conditioners and fixed air conditioners.

Of these air conditioners, some are one-piece and other splits (literally, separated).

The Monobloc air conditioner is composed of one piece, It extracts heat from the room where it is placed and vented outside through a drain pipe. It does the air as a room of modest size. It is for moderate use and the price of the unit is around 300 euros.

The split air conditioner, about 3 times more than the previous, includes an outdoor unit connected by piping to one or more interior components. The compressor is located in the outdoor unit and the evaporator in the country or from within. Advantages over single-piece, little or no noise and refreshed several pieces together if desired. The split air conditioner can also be reversible is to say that in winter, It will act as the heating system

Theair conditioning installation depends on the type of air conditioner must be retained, but generally, avoid installing air conditioning elements to sunny areas or near a source of artificial heat.

Installing portable air conditioner is a cinch. Packaged or split sometimes, they are mounted on wheels which gives them the great advantage that it can easily move from one room to another. The split is connected to the mobile unit outside on a flat duct via a window if necessary.

If the multi-split air conditioning installation is only for professionals, Fixed air conditioning installation can be performed quickly by a good handyman.

The indoor unit must always be positioned above the outdoor unit.

The steps for installing air conditioning

-Secure the bracket of the indoor unit on the wall
-Drill the hole through which pass the connection from the cold.
-Place the unit on its support and introduce into the hole, the power cable and hose.
-Attach the vent pipe vertically on the outside wall and the compressor on the ground (some also do not bind).
-Connect the power cable and connect the hose.
-If the air conditioning works, fill what's left of the hole with spackle.

Now it cool ? Sure still not fall below the 20 ° C. The transition from a high outside temperature to a temperature too cold causes headaches and colds !!

Reversible air conditioner

2012-07-31T09:58:00.001-07:00

In contrast du Reversible air conditioner, The functions of a conventional air conditioning and refrigerator are identical. They take all 2 heat from the ambient air to expel outside. Ambient air is captured either in the room to be conditioned or inside the refrigerator and the exhaust air is out of the room or behind the refrigerator.

It is through the intermediary of a refrigerant to the thermal properties such as specific heat exchanges are allowed.

In the case of a Reversible air conditioner, the circuit is reversed : heat from the outside is taken to be returned to the interior of the room.

The principle of operation of a reversible air conditioner is the same as that of a heat pump. The reversible heat pump air-water or water-water and Reversible air conditioner are 2 reversible systems that produce hot and cold.

Benefits of a reversible air conditioner

This is an economical heating system.

The refrigeration cycle of the air conditioner is simplified, it works with a favorable energy balance : for 1 KW absorbed by the compressor, the air conditioner product 2 KW cold but returns 3 KW heat.

The heat from outside air drawn in winter is multiplied by being released into the workpiece.

However, The COP, ie the coefficient of performance that allows for 1KW absorbed to recover 3, is a function of outside temperature course.

By focusing 2 features hot and cold (instead of in the case of a conventional air conditioning), the gain is evident not only from a financial point of view but also in terms of space occupied.

Disadvantages of a reversible air conditioner

1)The limits of power for the heating function.

No problem if the needs are modest. And revenge, more than the outside temperature is low, the higher the yield will decrease. That's why when large drops in temperature or in areas often exposed to cold, it is advisable to use an auxiliary heater and air conditioner properly handle its reversible. This does not pose a problem. The electronic heat is possible in the 10th grade on an air conditioning.

2)Noise

Even if they are more acceptable than those caused by a mobile air, the noise heard is that of a refrigerator. However, manufacturers are gradually improving their products to make them quieter.

The installation of the outdoor unit on a wall is not aesthetically, always the best effect.

The cost of an air conditioning system is reversible 10 to 20% higher than that of a cold air only.

The heat blast can cause discomfort and gene.

In brief, reversible if the air conditioner split is very suitable for use on a professional rather, he is more reserved for the off season in domestic households for performance reasons but also feelings of discomfort due to air movement.

Inverter air conditioner

2012-07-31T09:56:00.001-07:00

Unlike the inverter air conditioner, operation of a conventional air conditioning reflect the principle of "all or nothing".

As a refrigerator, air conditioning compressor running at full speed for a desired temperature. It reached, the air conditioning compressor continues to "turn" to restart later, when the temperature rises continuously and this.

This alternation of cycles on / off does not have a constant temperature and causes further, premature wear of the compressor, discomfort and energy consumption. Furthermore, at each stop of the compressor, humidity of the room rises sharply.

Designed in Japan, inverter technology air conditioning compressor and the VEV (Variable Speed), can overcome the disadvantages of the AC "all or nothing".

The control system, The DC Inverter Japanese Mitsubishi Electric has pioneered the design of air conditioning.

Inverter compressor VEV (Variable Speed) overcomes the slightest change in temperature by regulating the speed immediately when the internal temperature varies. Otherwise, if the temperature outside is high, it provides more power and conversely, moderate if it's warm outside.

A inverter air conditioner in fact similar to a variable speed air conditioner.

The advantages of inverter air conditioner

-A constant temperature
Printing drafts felt disappears and comfort is not commensurate with the conventional air conditioning.

-Increased longevity of compressors

-Savings on electricity bill can go beyond the 40% compared to traditional air conditioning.
Indeed, the inverter air conditioner start, reduces the current draw. Otherwise, Inverter system optimizes the setting constant temperature and accelerate at the start and holding it very precisely

-If the endless cycle of on / off (to 8 fois/heure !) of conventional air conditioning power consumption and generates significant discomfort, it can also cause damage to appliances by brownouts caused. The inverter air conditioner does not start him in that 1 2 fois/heure.times / hour

Inverter technology also applies to Reversible air conditioner (which produces cold in summer and warm in the cold) et en hiver, compared with electric heating, we see savings of up to 78% !

Caution still : the AC inverter uses a large number of electronic components. It is therefore very sensitive to variations of intensity and tension. It is therefore necessary to verify the electrical.

Inverter technology and its advantages are now well understood by all manufacturers of air-conditioning and even if its price is 10 to 20% higher than conventional equipment, Japan, 80% housing stock is equipped with air conditioning inverter and France, inverter air conditioner is recommended every season more.

car air conditioning

2012-07-31T09:53:00.003-07:00

The air conditioning system operation of a car is identical to that of a domestic air conditioning system.

The elements of a car air conditioning

A closed circuit containing a refrigerant R 134 A. This fluid has all the qualities essential for automotive air conditioning systems: non-flammable and chemically stable, it also blends easily with lubricants ...

4 basic elements of a car air conditioning:

-Air conditioning compressor. And disengageable belt driven, it allows the circulation of fluid in the circuit part and the general operation by compressing when in gaseous phase.

-The capacitor. It is placed in front of the cooling radiator and accelerates the transfer of heat by cooling the refrigerant.

-Regulator reduces the meanwhile, the fluid pressure and regulates its flow rate in the evaporator to ensure complete conversion of the liquid gas.

-The evaporator, is a heat exchanger that will transform the liquid into gas. It removes moisture and heat to the air so cold that happen in the cockpit of the car.

4 complementary elements of a car air conditioning:

It dehydrator it absorbs residual moisture of the circuit to protect it from corrosion, the brutal pressure changes and makes a pool of fluid in the liquid phase.

The thermostat-authorize or not the operation of the compressor depending on the temperature of the evaporator.

-Continuously monitors the pressure switch high and low pressures in the liquid phase of the circuit, for controlling the fan and the electromagnetic clutch of the compressor.

-The electromagnetic clutch. Driven by the pressure switch, thermostat, and the fuel injection systems, it prevents the air conditioning compressor to run continuously.

Maintenance of a car air conditioning

Nowadays, the automotive air conditioning is common. If the car air conditioner is more robust than in the past, it does not require a less correct and regular maintenance for an air conditioning system is not maintained may soon be detrimental to the health of passengers.

-Changing the air conditioning compressor belt and each revision of the dehydrator filter every 2 years.

Control of the charge of refrigerant. If leakage occurs, an operation of discharge and charge is to be performed by a specialist.

-Replacing the cabin air filter at least every two years.

-Verification of condensations leading to the discharge line which is located under the left front fender of the car in general.

-Setting the air conditioner thermostat car.

Hunting mushrooms often proliferate in the evaporator using appropriate antifungal products.

Tips

For your car aircon works optimally, some small reflexes are to be acquired.

-Reduce opportunities of thermal shock if possible (do not let not the doors of the car wide open even though the air conditioning is running for example!).

-Operate the air conditioner regularly to allow lubrication of the joints air conditioning compressor.

-Use air conditioning throughout the year. In winter, the air conditioning allows a very rapid demisting.

Have a good trip ...

Make the insulating capacity of his house

2012-07-31T09:49:00.005-07:00

Before setting up an air conditioning system in your home, it is necessary to achieve a heat balance to choose which air conditioning is best suited to your home and your needs.

Indeed, the establishment of an air conditioner increases your electricity consumption in a room of 15 to 25% depending on the use you make of it. In other words, if you install an air conditioner with power is not sufficient to cool the area concerned, your consumption will be even more important since the air conditioner will operate in overspeed for efficiency, ultimately, lower. If instead, you put up an air conditioner too strong, you made a purchase therefore unnecessary.

For the establishment of a one-piece air conditioner, it is possible to estimate the self-power required to condition part, in particular taking account of the surface thereof, the ceiling height, the number and dimensions of windows, the materials they contain but also on soil type. Also to take into account to establish your diagnosis: exposure of the room (south, north), the geographical location of your home, number of occupants therein and the presence of electrical devices capable of releasing heat (computer, oven, etc..).

For other air conditioning, you must hire a professional to determine what heat balance for free. Indeed, this assessment is an integral part of the installation and allow you at the same time to test the skills of your installer.

The importance of a serious and rigorous heat balance is thus proven. Send us your details now so we can prepare a custom quote and a free heat balance that will make your life fresh, even in summer!

air conditioning and filter: pure and fresh air

2012-07-31T09:46:00.000-07:00

The filter in your air conditioner is an essential element of the unit as a whole. Indeed, the filter cleans the air of dust, pollutants and allergens. In addition, the filter, and regular maintenance, play an important role in maintaining a working condition similar to that of the departure of the aircraft.
Thus, it is necessary and important to change the filter at least once in the month, after the air conditioner runs constantly. If the filter is not changed regularly, the air will not be purified and the device will deteriorate more quickly, costly repairs will be needed soon.
Currently, there are several types of filters:
fiberglass filters: these filters are mainly used in air conditioners. Single use, they must be changed every month.
fiberglass filters pleated filters: they are primarily used in residential or commercial complexes. The effectiveness of these filters is the density of the weave, but they do not adapt to all air conditioning systems.
electrostatic filters: they collect dust and microparticles through the static load of the air passing through them, they are ideal for people with allergies.
Electronic filters: they are connected to a power source and a pre-filter that collects the largest particles.
carbon filters: they are very effective against odor problems and are therefore recommended for individuals who own animals.
Together determine the type of filter that best suits you, leave us your details and we will establish specifications for units that will make your air fresh and clean!

Central air conditioning

2012-07-31T09:43:00.000-07:00

Central air conditioning is ideal for cooling different parts of your home. Currently, there are three variants of the central air conditioning system which depends on the state of construction of your home.
If your home is already built and you want to change your current air conditioning system or install a new one, you should opt for the multi-split system. The multi-split what is it? This is an air conditioning system which consists of several units: a refrigeration unit that is placed outdoors and several broadcasters, which can be ceiling, wall or other, which are placed inside your home. You can install up to eight indoor units, and thus cool the most important rooms in your home, and all manner of aesthetic and unobtrusive. With this system also, each piece is eligible for individual management.
If your future home is still under construction or about to be, you will have the choice between using a sheathed or system of floor heating / cooling. The air conditioning system, channel approaches the multi-split system described above. The floor heating system and its innovative and unique. This is a network of pipes under the floor which is used to circulate cold water through the summer and warm water in winter.
Whatever your decision between these three types of central air conditioning, it is important not to lose sight that these facilities are complex to implement and are therefore a professional know-how. Leave us your details and we will bring you quotes tailored to your needs and solutions for all your interior cool and well spend the summer cool!

The air conditioning system split

2012-07-31T09:41:00.002-07:00

The air conditioning system is different from the split system air conditioner piece in that it comprises at least two units. In this system, a first unit is placed inside and diffuse air was cool in the room where it is located. The second unit is placed outside the housing and serves to remove heat from the hot air. These two units are interconnected by a pipe commonly called the refrigeration link.
Depending on the number of room you want cool, you can install multiple indoor units, can now be called system split air conditioning. In the case mentioned above where there would be two units, there is a labor split or split mono.
This air conditioning system is one of the best available currently on the market with air conditioning and for several reasons. The first is that this system is composed of powerful and robust device that can cool a large room or several rooms. The second reason is that its devices can be mobile and, indeed, accompany you through the different rooms to be air conditioned. The third reason for the effectiveness of split air conditioners is that there is an outdoor unit, and therefore less intrusive sound indoors.
For more comfort and above all comfort for longer, it is important that you change your filters regularly split air conditioning.
The installation of your split air conditioning requires the intervention of a professional who can achieve a thermal balance with you and know that comply fully with planning rules. Send us your details now so that we can produce quotes and appropriate, make your wishes in air conditioning for your home possible.

The air conditioning monoblock

2012-07-31T09:40:00.000-07:00

The air conditioning system for general uses one-piece parts of a manageable size, usually for from 10 to space 30 square meters. This is an individual air-conditioning that works with a single unit which is located inside your home, there is no outdoor unit. In fact, the entire refrigeration system is in that unit, in a single block.
The only link of this air conditioning system with an outer sheath that can remove heat from indoor air outside. Installing such a system is quite easy, especially for mobile piece. Monobloc air conditioning installation is as simple as maintenance, cleaning and regular change of filters will allow your unit to run longer.
This cooling solution is available in three different versions.
First, the packaged air conditioning units portable, very easy to use since a simple electrical connection is enough to make them work. They should be placed near a window or door ajar to let the sheath. Monoblocks are sometimes fitted with wheels which can be moved to your desires sandstone.
Then, there are still packaged air conditioning units that have the same characteristics as the previous ones, without the ability to move them into your home, then they attach directly to the wall and are therefore part of the furniture.
Finally, there are one-piece window air conditioners. This type of air conditioner is the oldest. Installed above a window, they can sometimes cause noise disturbance to neighbors. Know before you install this type of air conditioner.
To get a quote quickly and easily adapted to your needs, leave us your details, it'll just think about where to position your air conditioner to imagine your piece and refreshing summer days to come.

The air conditioning system with gas

2012-07-31T09:36:00.000-07:00

The air conditioning system powered by a gas heat pump type water / water or air / water, it works in reverse and using natural gas. This type of conditioning is also often called reversible heat pump. This system can be coupled with a system of floor heating / cooling for more efficiency.
The operating principle is simple: heat from the air inside your home is taken even within this one, recovered by the refrigerant in your air conditioning and gas exhausted outside of your home. This last step is not mandatory since some air conditioning, gas heat can transform your indoor air component of the hot water in your home.
There are two varieties of gas air conditioners. The first consists of compression heat pumps. The compressor of this air conditioning system powered by a gas engine and not through an electric motor. The second variety of air conditioners is composed of gas absorption heat pumps. Here again, the gas, and here the gas burner, resulting in a thermochemical reaction and causes the refrigerant circuit that allows you to refresh your home.
Gas air conditioning has the advantage of not depending on outside temperature and thus ensures good performance throughout the year. Moreover, the fact that this system is reversible allows you to heat your home in winter, without having to install additional heating sources. Natural gas is cheaper than electricity, so you're going to offer you a nice holiday in the sun during the winter, then quickly send us your details to receive your personalized quote.

Solar air conditioning

2012-07-31T09:33:00.000-07:00

Solar air conditioning includes all techniques that use air as a primary energy source the energy delivered by the sun. Currently there are four different ways to produce cold from this solar energy. The first is to use photovoltaic panels to power an air conditioner with traditional electricity it needs. The second way to proceed is to convert solar thermal energy into mechanical energy associated with an air conditioner compressor. The third option to use the sun's energy to keep cool is that to use the same thermal solar energy to power, this time, an absorption cooling machine. The fourth and final possibility is using solar thermal energy to power an air conditioning system by evaporation.
The air conditioning system the most common, that is to say, the evaporative cooling, solar collectors used to provide heat to the absorption chiller. The latter, through a process of boiling, water dissociates and lithium bromide, which, after cooling and recombination, are distributed in a conventional air conditioning system.
The advantage presented by the different solar cooling systems is that they use renewable energy and totally free. Moreover, this is an opportunity to clean air as the fluids used to cool the air have no impact on the environment. Similarly, air conditioning that uses solar energy to reduce CO2 emissions in the atmosphere.
Solar air conditioning also has the advantage of providing more cold when it gets too hot, that is to say when the sun is present. You also enjoy the sun to cool off, spend a cool summer while protecting the environment, go for solar cooling. Leave us your details, we take care to make an estimate in line with your desires!

the refrigeration cycle

2012-07-14T07:10:00.000-07:00

Explanation of the refrigeration cycle: AB: A useful-overheating (rise in temperature which adds to the load of the compressor). As much as possible to avoid direct contact between the pipe and the ambient air through the suction pipe menginsulasi.BC: the compression process (gas under pressure and low pressure coolant temperature is increased so that the temperature more high coolant in the condenser in the process of compression is refrigerants have very high overheating .. CD: The process of de-overheating (coolant temperature has pemurunan, but did not alter the form, refrigerant is in gaseous form) DE: The condensation process (there is a change form refrigerant gas in a liquid without changing its température.EF: The method of sub-cooling in the condenser (refrigerant which is in liquid form is still throwing heat to the ambient air so that the temperature decreases). Very useful to ensure a perfect refrigerant state liquide.FG: The process of subcooling in the liquid line (fluid temperature liquid refrigerant is reduced as the temperature is always above the temperature of the ambient air). Guideline liquid is not isolated, so that heat transfer occurs in the air, are intended to increase refrigeration capacity. (Note: in some cases .. liquid pipes must be insulated ... later described in a separate discussion) GH: The process of expansion / pressure drop (in the form of a pressure liquid coolant is lowered so that the saturation temperature is lower than the ambient temperature is cooled, in order for the liquid refrigerant in the evaporator volatiles by absorbing heat from the air that is passed to the evaporator ) Changes in the form of liquid refrigerant into gas bubbles approximately 23% due to this pressure drop. So that leaves the refrigerant expansion valve / evaporator inlet as a liquid mixture is about 77% and 23% of bubbles gaz.HI: The evaporation process (low temperature refrigerant absorbs heat from the air that is passed to the evaporator There is a change in the form of liquid refrigerant in a gas There was also a decrease in the air outlet temperature of evaporator because of the heat absorbed by the refrigerant in the air.). IA: The evaporator superheat: gas refrigerant at low temperature is absorbing heat from the air, because the temperature is still below the air temperature. increase the coolant temperature). Overheating is useful to ensure the refrigerant in the form of a perfect gas before entering in the compressor

Some basic principles in cold / automobile air conditioning

2012-07-13T08:27:00.002-07:00

We see in the lives of everyday physical phenomena that seem simple and without interest, and yet ...Everyone has already seen a pot of boiling water!Well this is what happens in the evaporator of your car, water absorbs heat from the burner to 100 ° (1 bar air pressure) and then vaporizes the refrigerant contained in the evaporator absorbs heat from the air then evaporates (vaporizes the 134a, for a car, at 0 ° and 3 bar abs), this air being churned it emerges from the cold air!
We all at one time or another out a bottle of fresh water from the fridge (not to drink pastis! It is a sin!) That we can point out?Water forms on the bottle, it's happened?Well, in the form of moisture vapor in the air in the room and located closer to the cold bottle had its temperature lowered to pass from the vapor state to liquid state.We speak of condensation!
It happens the same with the refrigerant flowing through the condenser, using fans that churn the air through the condenser, the refrigerant is removed from heat to reach the point where it passes the vapor state, in liquid!
That's all c ... no?
The refrigerant circuit is a closed and sealed so that the state changes, as I just described, occur.
You must use a refrigerant that has adequate physical characteristics among others,it must evaporates at low temperature by absorbing heat.
For circulating the refrigerant compressor is used, the compressor draws vapor (because the liquid is incompressible) from the evaporator and compresses it to send it into the condenser:
Now it gets complicated a bit!
Some of you have heard of "the characteristic equation of ideal gas":
PV / T = constant
where P = pressure, V = volume T = temperature
I'll try to keep it simple: a compressor when the piston rises, the volume decreases in the cylinder so the gas pressure and temperature also increases (shown with a bicycle pump).
The ratio PV / T = constant is met.
If we suddenly releasing the pressure through a throttling valve, the pressure drops, the temperature drops and the volume increases, the ratio is still respected.
DO IN OUT ANY FLAME AWAY
Take a bottle of butane or propane full and open very, very slightly the valve. Put a metal plate to 10 cm in front of the valve for 2 seconds, the plate has become very cold.
The output pressure is low, its temperature and volume also increased (the outer volume is greater than the volume inside the bottle)It happens the same thing with the regulator of your installation:

The refrigeration cycle

1 - Condenser2 - Regulator3 - Evaporator4 - Compressor

Operation:In a refrigeration system fluid is drawn at low pressure and low temperature to the compressor. It is in vapor phase.The compressor compresses the vapor at high pressure and high temperature. The vapors pass from the vapor state in the liquid state in the condenser by evacuating heat. We are still in high pressure (HP) with warm temperatures and 100% liquid.
The fluid passes through the expansion valve where its pressure and its temperature drops, the fluid is in liquid low pressure and low temperature, the fluid passes through the evaporator where it absorbs the ambient heat and spend the liquid state in the vapor state always at low pressure and low temperature and again be sucked by the compressor.
I stop there for now. Feel free to ask questions if you feel the need!

repair refrigerating

2012-07-13T08:25:00.001-07:00

The experience of troubleshooting refrigeration installations on commercial refrigeration and air conditioning used to classify faults in refrigeration eight major families as follows
the first four failures are characterized by an abnormally low BP1 / the failure of the regulator too small (the power of the regulator is insufficient)2 / the fault of lack of support in FF (the refrigerant circuit does not contain enough of FF)3 / failure of the pre-expansion (pre-expansion reaction in the liquid line before the regulator)4 / failure of the evaporator too small (the cooling capacity of the evaporator is insufficient)5 / the fifth failure is characterized by a high BP with a low cooling capacity, it is too small compressor failure, compressor capacity is insufficient
the last three faults are characterized by an abnormally high HP6 / failure of the excess charge (it 's too much FF in the cooling circuit)7 / failure of the condensable (will have one large excess of noncondensable in the circuit)8 / failure of the condenser is too small (the condenser capacity is insufficient)
Whatever the breakdown, it is characterized by a refrigeration low compared to normal power.Failure of the regulator too smallIt is often a row has a bad selection of thermostatic expansion valve (nozzle too small). The regulator does not let enough of FF in the evaporator, the last drop of liquid will appear too very inside of the evaporator, the HS of the vapors leaving the evaporator will be important, the temperature of FF to the compressor suction is high and therefore the discharge of FF also.The compressor can suck more vapor produced in the evaporator, the BP becomes abnormally low. The compressor casing is abnormally hot.The BP has a tendency to decline while the temperature of the fluid to be cooled at the inlet of the evaporator increases, the maximum difference in temperature of the evaporator will be important.The condenser is potentially overkill and since the cooling power generated is low (lack of FF in the evaporator), the excess of FF is found in the condenser, the SR will be very good.
Do not confuse this with the failure of the pre-expansion which is characterized by a temperature difference between the departure of the liquid line and entering the valve.
When the failure of the regulator is located with certainty, it is necessary that the exact cause may be among the following causes:- Poorly chosen regulator- Valve closed too after a poor adjustment- Thermostatic expansion valve being drilled or planned for another FF- Regulator jammed mechanically- Filter entering the valve clogged ...Failure to lack of supportWhen lack of FF in the installation, it also lacks in all organs of the plant, particularly in the major organs.
The evaporator is poorly supplied with FF and impact than the failure of the regulator too small to be observed.
The condenser is overkill but it lacks FF in the condenser also, liquid line will be filled with evil, where the presence of FF gas in the piping, the SR will be virtually zero and bubbles will appear on the sight glass.
The presence of bubbles in the sight glass does not necessarily mean a lack of support in FF, however maque charge always results in the presence of bubbles in the sight glass.
Failure of the pre-expansion
This is a failure following a relaxation of FF on the liquid line before the regulator strictly speaking.For example when the filter-drier is clogged, it opposes the passage of liquid and FF can cause a large pressure drop (depending on the extent of clogging), this pressure drop can be comparable to that created by the "relaxation normal ", then we can find a mixture of liquid and vapor at the outlet of the filter-drier and sight glass is" bubbling ".It follows a lack of FF liquid entering the valve and hence inappropriate power FF of the evaporator with the same symptoms as the failure of the regulator too small. These differ in the two failures fact that there is a temperature difference in the liquid line for the breakdown of the pre-expansion.Failure of the evaporator too small
This failure characterizes all faults causing an abnormal decrease in the capacity of the evaporator. The evaporator produces less vapor that the compressor can aspire, the BP will decrease sharply.Exchanges between the FF liquid in the evaporator and the cooling fluid does not perform properly, the temperature difference of the fluid increases, the fluid is not cooled properly, the FF is not completely vaporized The HS is low and there's risk of stroke liquid, it is as if the regulator becomes overkill.The condenser is potentially overkill since the cooling power generated is low, the SR will be pretty good.
These failures may have two originsA-lack of air flow over the evaporator: the speed of circulation of the fluid (air) is low, the fluid (air) remains in contact with the exchange surfaces, the outlet temperature fluid decreases while the input increases, the temperature difference on the fluid is importantB-evaporator is dirty: the fluid is less well cooled and the temperature difference on the fluid is rather lowThe failure of the evaporator is too small can have several causes (air evaporator):- The tubes and fins of the evaporator are dirty- Air filters are dirty- The evaporator fan belt is broken or patina- Loss of network load of the evaporator airflow is too high- The traffic is bad in the cold- One of the evaporator fan not working- The evaporator fan is running backwards ...It should be noted that the direction of air flow is reversed to an axial type fan when the fan is running backwards, for a centrifugal fan, the flow direction remains unchanged; against by the airflow pressure and ventilation provided fall sharply.Compressor failure too small
     This failure includes all the deficiencies which may cause loss of compressor capacity.
    For example, when the compressor loses power (a two-cylinder operation, the other being off), everything asse as if the evaporator produces more FF vapor that the compressor can aspire, the BP will rise sharply.The mass flow of traffic in FF is reduced, the cooling capacity will decrease as well.The regulator is overkill and there's risk of slugging, the HS will be low.The amount of FF suction vapor is reduced, the compressor will be less well cooled and housing will be rather hot. The electrical energy consumed by the compressor will decrease.The condenser is overkill, the SR will be good.
      - The following list provides an update of some failures of the compressor is too small:- Broken or leaking valve- Broken valve- Compressor is undersized with respect to the evaporator ...Failure of the excess load
The thermostatic expansion valve adjusting the amount of FF in the evaporator, the favorite place for the excess charge is liquid and the bottle to a lesser extent the condenser.In case of excess charge, the liquid level in the bottle will increase and liquid in the condenser, thereby reducing the exchange surface of the condenser.Vapor condensation of FF will go wrong with repercussions on an increase in HP.By the FF against liquid that is in the condenser and liquid in the bottle will stay longer in contact with the coolant (atmosphere), which would assure a good SR.The increase in HP reduces the mass flow of FF sucked by the compressor and consequently a decrease in cooling capacity.The regulator is overkill because of the increase in HP and HS vapors at the outlet of the evaporator will be normal or low.
Note: If an operating pressure (BP or HP) varies in one direction, the other pressure always tends to vary in the same direction except for the small compressor failure or down while the HP BP increases.The increase in HP will lead to higher power consumption and the maximum temperature difference of the condenser will be rather high.It is preferable to testing of condensable not to confuse the failure of the excess charge with the failure of condensable, these two faults having substantially the same symptoms.Failure of condensableThe unwanted gases are condensable (air, nitrogen ...) that are in the refrigerant circuit.They are usually trapped at the top of the bottle and liquid they artificially increase the pressure HP (Dalton's law).The symptoms are the same as those of the breakdown of excess load. Only the test of condensable can differentiate these two faults.
The test is performed condensable as follows:1 - bring all FF liquid in the bottle (or condenser) by an operation such as "Pump Down"2 - forcing the circulation of cooling fluid (for example starting the condenser fan in the case of an air condenser) for some time (1/4 hour)3 - measuring the temperature of cooling fluid (air temperature in the case of an air condenser)4 - compare this temperature indication of the temperature of the manometer HP- If the respective indications of HP pressure gauge and thermometer coincide approximately 2 ° C, there is no condensables in the refrigerant circuit- If the temperature gauge reading is more than 2 ° C warmer than the thermometer, it there's traces of condensable which are even more important that the gap is larger- If the temperature gauge reading is less than 2 ° C warmer than the thermometer, it means that the circuit is loaded with FF, see completely empty
Purging is possible when the bottle includes a liquid trap e upper or creating a drain on the inlet fitting if it is not soldered.Otherwise, empty (recover), to evacuate and recharge the system in FF.Failure of the condenser is too small
This failure characterizes all faults causing an abnormal decrease of the condenser capacity. The condenser can no longer ensure a good cooling vapors FF, HP will increase significantly.The vapor exchanges between the condenser and FF in the cooling fluid does not perform properly, the temperature of the coolant at the outlet of the condenser as well as decreases the temperature difference on the fluid. FF vapors are not fully condensed and the SR is very low or nonexistent. In some cases, even the sight glass can "chill out" while the burden is correct in FF.The increase in HP reduces the cooling capacity and it is as if the regulator becomes overkill, the HS will be normal or low.Because of the high HP, the power consumption of the compressor is greater and the mass flow of FF pumped by the compressor decreases.The compressor suction within FF it may, the BP will increase.These failures may have two origins:- A - the lack of air flow over the condenser: the speed of circulation of the fluid (air) is low, the fluid (air) remains in contact with the exchange surfaces, the outlet temperature the fluid increases, the temperature difference on the fluid is important-B-is dirty the condenser: the temperature of the fluid at the outlet of the condenser is lower than normal, the temperature difference of the fluid will be rather weakThe failure of the condenser is too small can have several causes (air condenser):- Tubes and condenser fins are dirty- The location of the condenser is a misnomer- The condenser fan belt is broken or patina- Loss of network load of the evaporator airflow is too high- Will have one recycling of hot air over the condenser- One of the condenser fans not working- The evaporator fan is running backwards ...Synthetic scheme refrigerated failures

The Cold Rooms

2012-07-13T08:23:00.003-07:00

A cold room is a different construction of other industrial buildings as it is meant for conservation (storage) products for a long time maintaining a low temperature.
Depending on the temperature we find two types of cold rooms:
- The positive cold rooms.
- The negative cold rooms.

But according to the construction there are three categories:

1) removable prefabricated cold rooms:
These are isolated local where all surfaces are made of sandwich panels prefabricated in the factory and can be assembled and disassembled repeatedly. Often the panels are equipped with eccentric system of locks operable by key close and clamp the two panels to each other with the addition of a seal between the two

demountable prefabricated cold rooms:
These are rooms where at least one wall is made of prefabricated sandwich panels at the factory then assembled on site permanently without metal frames and locks system.

the walls are built of masonry, insulation is then a dubbing for decreasing the heat transfer. Except that provision requires the establishment of a screen to protect the insulation steam in addition to a system for fixing the latter on the walls.A] The insulation of Cold Rooms:

Isolation is the main element that enters the construction of cold rooms, whatever their nature, since it promotes resistance against heat transfer heat from the hot environment to a cold environment. Thus a good insulator must have the following characteristics:
- Conductivity coefficient (λ) small.
- Low dimensional variation.
- Impermeability to water vapor.
- Low Cost.
- Flammable or with a low reaction to fire.
- Easy to work and carry.
- Not alterable by microorganisms (fungi, insects, pests ...).

The VRV systems "The air conditioning refrigerant flow variable"

2012-07-13T08:16:00.003-07:00

Principle of operation

We knew the principle of "DX" (the evaporator of the refrigerating machine directly cools the air in the chamber air handler). This time, we realize the direct expansion in each room because the coolant is transported to the interchange of premises used evaporator! It is neither air nor water flowing through the pipes, but the refrigerant.

From an outdoor unit, it can power up to 32 indoor units. Outside groups available on the market today have cold powers ranging from 15 to 90 kW in compact for connecting an independent refrigerant circuit. These can be multiplied, provided that the space available for outside groups are present. But these are facilities that will then operate in parallel (no exchange between circuits connected to different outdoor units).

This system can operate in three diet:
* Operation in cooling only
* Reversing mode (cold or hot)
* A heat recovery (hot and cold simultaneously)

In the outdoor unit is a variable speed hermetic compressor (scroll compressor or rotary compressor), with a regulation "INVERTER", ie variable speed by adjusting the supply frequency. allowed to quit a good control of flow rates of fluids and good mastery of electricity especially in the summer or the need for electrical energy is increased [

Refrigeration compressors (scroll, rotary)

2012-07-13T08:14:00.001-07:00

In the refrigeration industry, two distinct families appear:
Positive displacement: Compression is achieved by reducing the internal volume of a compression chamber.
There are compressors:
A pistonA screwA spiralRotaryCentrifugal compressors: These are rotary machines in which the compression of gaseous FF mainly due to the centrifugal force
II. THE ROTARY AND SPIRO-ORBITAL
II.1 The rotary compressors
1. Operating principle
The rotary compressors consist of a "piston" (called turning or rolling) and one or more pallets. Compression is achieved by volume reduction between the "piston" and the palette.
There are rotary compressors:
A rolling pistonA palleta) The rotary rolling piston compressor
It consists of a stator within which is arranged eccentrically a rotor (piston). A palette is mounted on the stator. Compression is achieved by volume reduction.
b) The vane rotary compressor
It consists of a cylindrical stator within which is arranged eccentrically a rotor (piston). Pallets are mounted on the rotor.
2. Advantage over a piston compressor
It can be mounted in any position
He has a couple regular
Robust

II.2 The scroll compressors (scroll)
1. Operating principle
Compression is accomplished through two spirals nested one inside the other. A spiral is fixed and the other is driven in an orbital motion. This movement creates pockets of gas that are displaced and compressed to the discharge port.
2. Advantages over a rotary compressor
Number of moving parts reduces
Low vibration, quiet
Low starting torque
Absence of valves (only one non-return valve located in the discharge connection)
Supports slugging
Very high volumetric efficiency

PRINCIPAL ORGANS OF A REFRIGERATION MACHINE

2012-07-13T08:10:00.001-07:00

The refrigerating machine vapor compression consists of 4 main organs that are:

- The compressor

- The condenser

- The valve

- Evaporator

The refrigerant describes a closed cycle in four phases through the circuit consisting of the principal organs:

- Compression of the gaseous fluid

- The condensation of the gaseous fluid

- The expansion of the fluid liquid

- Vaporization of liquid fluid (cold production)

Figure 3.0: Basic diagram of a refrigerating machine.

The compressor draws the refrigerant gas (low level of temperature and pressure) from the evaporator, compresses it to a higher level of temperature and pressure and then delivers it to the condenser.

http://www.2ie-edu.org/cours/techniques_frigorifiques/images/vues_compresseur_hermetique.JPG

Figure 3.1: Views of hermetic compressor.

The condenser is a heat exchanger which will enable the evacuation of the heat contained in the gaseous refrigerant from the compressor in the liquefying. This condensation (liquefaction) is obtained by cooling the gas refrigerant at constant pressure by a medium that can be water or air.

This heat removal is done in three steps:

- Superheating of the refrigerant vapor (sensible heat removal - section AB)

- Vapor condensation (latent heat evacuation - main stage - section BC)

- The subcooling of liquid refrigerant (sensible heat removal - section CD)

The regulator reduces the pressure of the refrigerant liquid (creation of pressure drop) from the condenser before its introduction into the evaporator in order to allow its evaporation at low temperature in the evaporator.
It also regulates the amount of liquid refrigerant entering the evaporator according to the needs of "cold" (only for thermostatic expansion valves).
For capillary type regulator (capillary tubes), the refrigerant flow arriving in the evaporator is the inside diameter (0.6 to 1.5 mm) and length (from 1.80 to 3.50 m) of the tube and the pressure difference between the condenser and the evaporator.

http://www.2ie-edu.org/cours/techniques_frigorifiques/images/detendeur_capillaire.JPG
Figure 3.3: Pressure capillary.

The evaporator is a heat exchanger wherein the liquid refrigerant of low temperature and pressure will absorb the heat of the medium to be cooled (air or water) at constant pressure thus becoming gas.
This absorption of heat takes place in two stages:
- Evaporation of liquid refrigerant (suction latent heat - main stage - section AB)
- Overheating of the vapors from the evaporation of liquid refrigerant (suction heat sensitive - section BC)
http://www.2ie-edu.org/cours/techniques_frigorifiques/images/evaporateur.JPG
Figure 3.4: Evaporator.

This refrigerant gas is again absorbed by the compressor and the cycle resumes.

3.2 THE COMPRESSORS

3.2.1 Technology compressors

There are two main types of compressors Steam:
- The displacement compressors in which the vapor compression is achieved by reducing the volume inside a compression chamber, this type of compressor is the most common of refrigeration plants.
- Centrifugal compressors also known turbochargers where the compression resulting from the centrifugal force produced by dynamic training using a paddle wheel is a type of compressors for specific applications and used to great powers (refrigeration units high power in HVAC for example).

3.2.2 Positive displacement

There are several types of superchargers and the classification used to distinguish:
- Reciprocating compressors, the best known is the AC compressor piston is the type of compressor most common; vapor compression is achieved by moving one or more pistons in a given capacity (cylinder); we should also mention the axial piston compressors (compressor swash plate) encountered mainly in the field of automotive air conditioning
- Also called rotary compressors vane compressors in which the compression of the vapors is obtained by displacement of a hollow cylindrical body of an eccentric mass acting on a movable blade
- The scroll compressors also known scroll compressors in which the compression of the vapors is obtained by the rotation of a movable scroll a fixed scroll in
- Screw compressors which must be distinguished from the single screw compressors (single rotor) and twin-screw compressors (two rotors)
3.2.3 Centrifugal compressors

A centrifugal compressor is a turbomachine which communicates energy to the refrigerant through one or more wheels rotating in a casing: the kinetic energy resulting from the centrifugal force is then transformed into static pressure in a channel section which increases called volute.

3.2.4 Compressor Engine Association

When we speak of compressor, it implies motorcycle compressor, the compressor being driven by the mechanical part an electric motor.
Depending on the type of connection or association between the two parts are distinguished:
- Hermetic compressors
- Open compressors
- The semi-hermetic compressors or semi open

3.2.4.1 The hermetic

The electric motor and compressor are enclosed in one envelope and unavailable "in principle" to each part in isolation, the assembly is supported generally by springs to prevent vibration transmission.
The compressor draws refrigerant vapor within the envelope and the discharge is performed through a flexible tubing brazed to the casing.
The electric motor is powered by son with terminals sealed.
The tightness of these compressors is provided by fixed joints (passage son and piping).
This type of compressor is used for low power (refrigerators, air conditioners ...) and medium power (liquid chillers, cooling cabinets ...).

3.2.4.2 The open compressors

The electric motor and the compressor are associated by a connecting member which can be a coupling sleeve or one or more belts.
Access to the various components of the compressor as well as those of the engine is possible.
In this type of compressor, the rotational speed is adjustable and modifiable by changing the motor pulley example, however this type requires a rotating seal (rotary joint) to the crossing of the housing by the shaft. It is used for all power.

3.2.4.3 The semi-hermetic compressors or semi open

This is an intermediate type between the previous types. The electric motor and compressor are mounted on a common shaft and on the same frame with the possibility of access to each element, so that these compressors are also called hermetic "accessible." Accessibility is carried out by bolted plates on the frame. This type benefits from the advantages of the open group (access mechanism) and the group sealed (no seal).
They are used for middle powers.

air conditioning

2012-07-13T08:05:00.001-07:00

Air conditioning is the technique of modifying, controlling and regulating the climate (temperature, humidity, dust levels, etc..) A place for comfort reasons (offices, houses) or for technical reasons (laboratory medical, local manufacturing of electronic components, operating theaters, computer rooms).
The main features are modified, controlled or regulated are:

     the degree of pollution of ambient air (room to be treated): renewal, either by forced extraction of air from the room, either by forced introduction of fresh air (outside air) in the room or by partial replacement of ambient air pollution (addition of a mixing box).
     the air temperature: modification by season (heating or cooling),
     the humidity of the air treated: humidification or dehumidification
     the dust content of the air filtration treatment of the air blown or taken,
     maintaining constant indoor conditions (control).

While heat and humidity rise within elementary techniques, chill and dehumidify the air require sophisticated techniques. In practice, we mainly discuss conditioning in these last two objectives.
The air conditioning is essentially the technique of heat pumps and is increasingly associated in one device, a "reversible air conditioner" (summer cooling, winter heating).

Air conditioning: the principle of operation

2012-07-13T08:01:00.001-07:00

In all air conditioning systems, the principle of refrigeration is identical. It is well known, the cooling circuit of our refrigerators which has the feature of extracting energy from a "cold environment" (indoor) to be discharged into a "hot medium" (outside air). The operation of an air conditioner is based on the phase change of a refrigerant: evaporation takes place with heat absorption, its condensation with generation of heat. Any air conditioner thus includes:
- Exchanger evaporator (1) where the cooling of evaporation of the refrigerant is sent to the air.
- A compressor (2) compressing the gaseous fluid, increasing its pressure and temperature.
- A condenser exchanger (3) where the gas in condensing gives up its heat.
- A regulator (4) is carried out where the decrease in pressure of the liquid refrigerant before it evaporates in the heat exchanger.

In cooling mode: The evaporator cools the room air treated, the condenser gives up its heat or air outside or water network.
In heating mode: A four-way valve (5) to reverse the cycle, the condenser becomes évaporteur becomes evaporator and condenser. The condenser then heats the room air treated, the evaporator absorbs heat from outside air. If the power in heating mode is not enough, the electric résisances can be used to provide the necessary complement.