Climate Controls

Heater

Before activating the heater, open the heater valve on the rear/right side of the engine block (1).. Under most cold-weather conditions it is not necessary to have the valve completely open..

During hot weather, shut the heater valve off.. This will ensure that no engine coolant will flow into the heater core..

Make sure the air conditioner is deactivated except during defrosting.. To increase the cab interior temperature for cold weather operation, start the engine and make sure the coolant temperature bar graph indicates two or more bars.. Rotate the temperature control switch (3) to increase the temperature.. Adjust the fan speed switch (4) to increase or decrease air flow..

Air Conditioning Operation

CAUTION: THE AIR CONDITIONING SYSTEM USES R134A REFRIGERANT. DO NOT MIX WITH OTHER REFRIGERANTS. DO NOT ATTEMPT TO TOP OFF THE SYSTEM WITH ANY OTHER REFRIGERANTS. CONSULT A QUALIFIED TECHNICIAN FOR ALL AIR CONDITIONING REPAIRS.

The climate controls consist of a rocker switch (2) which activates the air conditioning, and two rotary switches, controlling the temperature (3) and the pressurizer fan (4)..

Depress the top of the air conditioning rocker switch

(2)to activate the air conditioner.. Depress the bottom of the switch to deactivate the air conditioner..

The temperature control switch (3) is used to maintain a constant temperature.. Rotate the temperature control switch counterclockwise to increase cooling.. Adjust the fan speed switch (4) to increase or decrease air flow..

To aid in defrosting the windshield and side windows the air conditioner and heater may be operated at the same time.. The air conditioner will remove moisture from the air while the heater warms the air in the cab.. When the windows are clear, deactivate the air conditioner..

3-21 Section 3 - Operation Cab Controls & Instruments

1

F3-21

2 3 4

AUTO TEMP CONTROL

F3-22

435/485/535