11.5.2. Features of system of heating and ventilation of motor vans of GAZ-2705 of "Kombi" and buses

Fig. 10.25. Control panel of heating and ventilation

In system of heating of the specified cars the electric pump providing increase in a consumption of liquid in system that improves warming up of a cabin is used. The electric pump is installed in the drain highway of system of heating under a cowl, on the right longeron. Turning on of the electric pump is carried out by switches 2 and 4 (see fig. 10.25) on the OVU control panel. For turning on of the electric pump it is necessary to install the handle 2 in one of three provisions and to turn on the heater crane turn of the handle 4 (clockwise) from extreme left situation. In operation the electric pump of service does not demand.
The electric pump is not subject to repair; at failure it needs to be replaced. Breakage of the electric pump worsens work (thermolysis) of OVU, but does not interfere with circulation of liquid in system.
In system of heating of motor vans "Kombi" and buses the additional heater is also applied.
It is located: in buses on 6 places and motor vans of "Kombi" on a floor for (or under) a passenger seat of a cabin; in buses on 10 places — on a floor under a seat in a forward part of passenger salon.
The device of an additional heater is shown in fig. 10.27. The radiator 3 additional heaters is consistently connected to a radiator of the main heater hoses. The additional heater works in the mode of use of internal air. Numerous passing of internal air through a radiator of an additional heater provides high intensity of warming up of a cabin of GAZ-2705 of "Kombi" or inside of buses.
The fan of an additional heater has three speeds of rotation. Turning on of the fan is carried out by the handle 3 (fig. 10.25) the regulator of amount of the air coming to interior of cars. The handle of the regulator has four provisions:
- it is included;
- minimum productivity of the fan;
- average productivity of the fan;
- maximum productivity of the fan.
Ventilation of a cabin
Compulsory forced ventilation is carried out similarly specified for motor vans with one row of seats (at the closed windows of sidewalls of a body of buses and the closed roof hatch).
The exhaust ventilation is carried out through cracks on internal panels in the lower part of doors of a cabin, via the roof hatch, and also through air vents on back racks of sidewalls of buses and windows.
Electric motor of the fan of an additional heater
The fan of an additional heater brings into rotation the bipolar electric motor with excitement from permanent magnets.
Technical characteristics of the electric motor
Type..... 197.3730
Power, W..... 60
The consumed current at loading the fan, no more, And..... 8,5
Frequency of rotation of an anchor at loading the fan, min.-1..... 3800
Axial side play of a shaft, no more than a mm..... 0,8
Maintenance and repair of an additional heater
Service of an additional heater consists in its periodic survey.
At dribble of cooling liquid it is necessary to improve collars of hoses in places of connections of hoses. Dribble of liquid from a casing of a radiator of a heater testifies to leakage of a radiator; in this case it needs to be removed and repaired or replaced.
Removal of a radiator is made in the following order:
- to merge a part of cooling liquid from the engine cooling system (about 5 l);
- to disconnect hoses from tubes of a radiator of an additional heater and to merge the remains of cooling liquid;
— to unscrew two screws of fastening of a plastic protection and to remove a protection;
- to disconnect two spring brackets 4 (fig. 10.27) and to uncover 1 casing;
- to take out a radiator 3 of a casing 2.
The removed radiator needs to be checked for tightness in a water bathtub with an excessive pressure of 1 atm. To eliminate leakage of a radiator with preload of otgibochny short moustaches as it is specified for a radiator of the main heater.
The electric fan does not work
If at inclusion of a heater the electric fan does not work or works with the increased noise, it is necessary to be convinced of serviceability of the electric motor and reliability of fastening of the fan.
You make removal of the electric fan in the following order:
- to remove a heater protection;
- to turn off four bolts of fastening of a cap 8 (see fig. 10.27) an air duct to a casing 2 heaters;
- to take out the electric motor 9 with the fan 6;
- to remove the fan 6 from the electric motor, having turned out two screws 5.
To examine the fan and in case of existence of cracks, chips etc. to replace it.