Belarus 820 - Cab Heater and Fan Control

80-0000010B OM
29
2.4 Cab heater fan control
Elements of heater fan control are shown in figure 2.4.1.
1, 2 – heater valve handle; 3 – recirculation screen; 4 – cab fan switch; 5 – deflector;
6 – hose; 7 – clamp; 8 – drain plug.
Figure 2.4.1 – Elements of heater fan control
Cab fan heater can operate in two modes: heating and ventilation.
In order to actuate the heater fan in heating mode it is necessary to perform the fol-
lowing:
- start the engine and let it operate at medium rpm for warming-up coolant up to
the temperature from + 70
0
C to + 80
0
C, then open the heater valve. To do this, turn valve
handle 1 (fig. 2.4.1) anticlockwise against the stop. If the heater valve is mounted outside
the cabin, then it is necessary to turn handle 2. Then increase engine speed and in 1…2
minutes make sure that coolant circulates through the heater radiator, by opening slightly
drain plug 8 of the drain valve from the right side of the cabin;
- check and, if necessary, refill the expansion tank with coolant to the upper edge of
the expansion tank fastening clamp;
- switch on the heater fan with the help of switch 4. Within 1-5 minutes warm air
starts filling the cab, which demonstrates heating system integrity;
- direct the air flow in the right direction with the help of deflectors 5;
- the volume of air ventilated into the cab can be controlled by opening recirculating
screens 3.
In order to drain the coolant from heating system, drain plugs 8 are provided on the
left and right sides of the cabin.
With valve 1 installed (figure 2.4.1) drain coolant from the heating system in the fol-
lowing way:
- open the heater valve, to do this turn handle 1 against the stop anticlockwise;
- drain coolant into special reservoir, opening drain plugs 8 from the left and right
sides of the cabin.