8.4.3. Depression creation in system

NOTE When opening system depression for protection against air and moisture hit is necessary to create each time. After installation of any element it is necessary to support depression in system approximately within 15 minutes. The elements of system opened for repair should be under the influence of depression within 30 minutes.

If the engine does not work, carry out the following procedures.

Fig. 8.60. Situation "is closed"

Attach a set of control manometers to compressor unions. Close gates of lines of high and low pressure (fig. 8.60).

Be convinced that the coolant from system is merged.

Attach the central hose of a set of manometers to an entrance branch pipe of the vacuum pump.

Turn on the vacuum pump and open gates of high and low pressure.

Approximately through 10 mines be convinced that the manometer of low pressure shows depression below 94,39 kPas (0,96 ^kgfs/cm2). If it is not possible to receive depression, it indicates a system leakage. In this case eliminate a leakage, as shown below.

1. Close both gates of a set of manometers and switch off the vacuum pump.

2. Charge system a coolant from capacity (about 0,4 kg).

3. Define a leak place by a techeiskatel.

4. Again merge a coolant and create depression in system. If leaks it is not revealed, continue to create depression in system.

Turn on the vacuum pump.

Open both valves of a set of manometers until depression of 94,39 kPas (0,96 ^kgfs/cm2) (fig. 8.61) will be created.

Fig. 8.61. Situation "is open"

After the manometer of low pressure will show depression about 94,39 kPas (0,96 ^kgfs/cm2), continue to create depression within 15 minutes.

After 15 mines of finding of system under the influence of depression close both gates of a set of manometers and switch off the vacuum pump. Disconnect a hose from the vacuum pump. The system is ready for a charging a coolant.

Fig. 8.62. The installation scheme at action with the gate of a charging of system

Before connection of the gate to capacity with a coolant turn its handle to the full counter-clockwise.

Establish a disk in extreme top situation by rotation counter-clockwise.

Attach the central hose to the gate union.

Rotation of the handle of the gate clockwise punch an opening in a tight top part.

Weaken an inhaling of a nut of fastening of the central hose to the central union of control manometers.

Let the air out within several seconds, then tighten a nut.

Establish the capacity gate with a coolant in the situation specified above in the section «Actions with the gate of a charging of system».

NOTE This operation is carried out for a system charging by a coolant in a vaporous condition through a contour of low pressure. At the vertical provision of capacity with a coolant the last moves in system in the form of steam.

Open the gate of a contour of low pressure and adjust its situation so that pressure on a manometer of low pressure did not exceed 412 kPas (4,2 ^kgfs/cm2).

That pressure паров in capacity with a coolant slightly exceeded pressure in system, place capacity in a vessel with warm water (temperature about 40 °C).

Start the engine on accelerated single to a course and turn on the conditioner.

NOTE Capacity with a coolant keep in vertical situation to exclude hit of the liquefied coolant in system through the absorption line that can cause compressor damage.

Fig. 8.63. Situation "is closed" a contour of low pressure

Fill system with demanded quantity of a coolant then close the gate of a contour of low pressure (fig. 8.63).

Quantity of a filled coolant: 500 ±25.

At the lowered speed of filling by a coolant ship capacity with a coolant in warm water (temperature about 40 °C).

ATTENTION By no means on immerse capacity with a coolant in warmed-up water in temperature above 52 °C. It is forbidden to warm up capacity a blowtorch or in the drying chamber.

After a vacuum purge of system completely close gates of high and low pressure.

NOTE This operation is carried out for a charging of the discharged system by a coolant in a liquid state through a contour of a high pressure. At the provision of capacity upside down the coolant moves in system in the form of liquid.

ATTENTION It is forbidden to make a system charging through a contour of a high pressure at the working engine. At a charging a liquid coolant the gate low pressure do not open.

Establish the capacity gate with a coolant in the situation specified above in the section «Actions with the gate of a charging of system».

Completely open the gate of a high pressure, having placed capacity with a coolant in situation upside down.

Charge system demanded quantity of a coolant, defining its weight by scales. The excessive charging will lead to excess of pressure of forcing (in a contour of a high pressure). Upon termination of a charging close the gate of a high pressure.

Quantity of a filled coolant: 500±25.

After a system charging demanded quantity of a coolant close the gate of control manometers.

By means of a techeiskatel be convinced of absence of leaks from system.

NOTE Before removal of control manometers it is recommended to check system work.

In all cases when existence of leakage of a coolant is supposed or the works connected with a detachment of elements or weakening of an inhaling of connections are performed, carry out check of tightness of system by means of an electronic techeiskatel.

Check the moment of an inhaling of connections of pipelines. When weakening an inhaling tighten connections by the specified moment. By means of a techeiskatel be convinced of absence of leakages of gas.

If after a connection inhaling leak is not eliminated, discharge system, separate connection and check condensing surfaces on existence of damages. Even slightly damaged details of connections are subject to obligatory replacement.

Check amount of compressor oil and if necessary restore it to norm.

Charge system and check its tightness. If leaks it is not revealed, make a vacuum purge and a system charging.

Establish control manometers.

Start the engine and leave it to work at frequency of rotation of a cranked shaft of 2000 ^mines-1, establish the temperature switch in the situation corresponding to giving in salon of most cooled air, and the fan switch – in the situation corresponding to the maximum speed of rotation.

Open all glasses and doors.

Fig. 8.64. Installation of the dry thermometer in a giving nozzle in salon of the cooled air

Place the dry thermometer in a giving nozzle in salon of the cooled air (fig. 8.64).

Place психрометр in a place of a fence of air in a refrigerating contour of the conditioner.

Check indications of a manometer of a high pressure which should be within 1,373–1,575 kPas (14–16 ^kgfs/cm2). If indications exceed the top specified limit, water a kondensor. If indications are lower than the bottom limit, cover a forward part of a kondensor.

Check indications of the dry thermometer which should be within 25–35 °C.

Fig. 8.65. Psikhrometrichesky schedule

Determine relative humidity of air by the psikhrometrichesky schedule by a way of comparison of temperatures on the moistened and dry thermometer психрометра, the fence of air placed in a place in the conditioner (fig. 8.65).

NOTE Having determined values of temperature by the moistened and dry thermometer on an evaporator entrance, it is possible to define relative humidity of air. Example: the temperature on the dry and moistened thermometer on an entrance of the evaporator makes according to 25 °C and 19,5 °C. The point of intersection of the corresponding dashed lines on graphics gives value of relative humidity (60 %).

Determine temperature by the dry thermometer placed in a snivel of supply of cooled air in salon and calculate a difference of values of temperature on the dry thermometer on a fence of air and on the dry thermometer on an air outlet in salon.

Fig. 8.66. Schedule of calculation of relative humidity

Be convinced that the point of intersection of lines of relative humidity and a difference of temperatures is in limits painted over black areas that points to compliance of characteristics of holodo-productivity to norm (fig. 8.66).