page 59
295 AC
800-00158
AIR CONDITIONER MAINTENANCE CONTINUED...
RUNNING THE UNIT AS PREVENTIVE MAINTENANCE
Run the air conditioner for a while every two weeks or so even in cold weather. If the unit is unused for long periods of
time, seals shrink and components become stiff. Running the unit is an easily performed procedure which can help
prevent future problems.
FRESH-AIR INTAKE FILTER
This filter is located under the cab and allows the air conditioner unit to draw fresh air from outside the cab for
circulation.
Change the filter once per year when operating in normal conditions. Use a shorter change interval when operating in
very dusty or dirty conditions.
To change the filter, remove the clamp. Filter is pressed onto an elbow - pull filter off and replace with a new one. This
is a disposable filter and should
not be cleaned and reused.
RECEIVER/DRYER INSTALLATION
When installing/replacing the receiver/dryer, always install it in a vertical position (with sight glass and fittings at the top)
in order for the heater/air conditioner to work properly.
CONDENSER INSTALLATION
The condenser must be installed with the ports at the top. Installing the condenser with the ports at the bottom will
flood the compressor with coolant and ruin it.
AIR CONDITIONER TROUBLE SHOOTING
The following is not intended as a comprehensive set of trouble shooting rules for air conditioning systems, but as a
"check-first" list to find the problem.
For a complete trouble shooting guide, obtain a copy of Red Dot’s Heavy Duty Vehicle Air Conditioning and Heating
Systems - Service Manual (Red Dot part no. RD-5-5900-0)).
Symptom:
Poor or no air conditioning:
1) Ensure that machine is in no-heating condition (close water valves to heater on engine). Run machine for a
while with air conditioner and fan on. Check to see if unit is cooling.
a) If unit is now cooling:
1) water valve needs service/replacement or,
2) water control unit needs service/replacement.
b) If unit is still not cooling:
1) check sight glass on dryer - should be green to yellow. If yellow to brown, replace dryer. If ok,
2) check air conditioner electrical circuit as listed below.
Air Conditioner Electrical Circuit Check:
1) Check if 12V is at air conditioner control.
a) If no, check 12V supply.
b) If yes, check if power is at terminal B when switch is on. If no, replace switch. If yes,
To Next Page
Loading...