Driver Controls and Instruments 1 2 3 1 2 3 1 2 1 2 3 3 01/19/2000 f830367b 4 5 05/16/2000 f830397b 4 5 1. Fan Switch 2. Air Selection Switch 3. Temperature Control Switch 4. Air Source Lever at the Fresh Air Position 5. Air Conditioning On/Off Lever at the Off Position 1. Fan Switch 2. Air Selection Switch 3. Temperature Control Switch 4. Air Source Lever at the Fresh Air Position 5. Air Conditioning On/Off Lever at the On Position Fig. 3.35, Defogging and Defrosting Settings Fig. 3.36, Heating Settings 4. When a comfortable temperature has been reached, adjust the fan switch setting and tempera- ture control switch as needed to maintain the tem- perature. NOTE:
To increase the flow of warm air to the floor, close the dash-face outlets. Air Conditioning Using Fresh Air IMPORTANT: If equipped with air conditioning, do not operate the heater and air conditioning system with the air source lever in the recirculation mode for more than 20 minutes. This will prevent the buildup of fumes or odors inside of the cab (for example, from smoking). IMPORTANT: Operate the air conditioner at least five minutes each month, even during cool weather. This helps prevent drying and cracking of tubing seals, reducing refrigerant leaks in the sys- tem. Operate the air conditioner only after the en- gine compartment is warm, and the interior of the 3.48