MacDon M1170 Operator's Manual page 431

Problem
Symptom: Air conditioning cools intermittently.
Unit icing up due to thermostat
adjusted too low
Unit icing up due to excessive
moisture in system
Unit icing up due to incorrect super-
heat adjustment in the
expansion valve
Thermostat defective
Defective blower switch or
blower motor
Partially open, improper ground or
loose connection in compressor
clutch coil
Compressor clutch slipping
Symptom: Air conditioning system too noisy.
Defective winding or improper
connection in compressor clutch coil
or relay
Excessive charge in system
Low charge in system
Excessive moisture in system
Loose or excessively worn drive belt
Noisy clutch
Noisy compressor
Compressor oil level low
Blower fan noisy due to
excessive wear
Symptom: Cab windows fog up.
High humidity
214733
TROUBLESHOOTING
Solution
Adjust thermostat.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
Tighten or replace as required.
Remove clutch for service or
replacement as required.
Check mountings and repair. Remove
compressor for service or
replacement.
Add SP-15 PAG refrigerant oil.
Remove blower motor for service or
replacement as necessary.
Run A/C to dehumidify air and heater
to control temperature.
415
Section
Contact Dealer.
—
—
—
—
—
—
—
—
—
—
Tensioning Air Conditioner (A/C)
Compressor Belts, page 362
Replacing Air Conditioner (A/C)
Compressor Belts, page 363
Contact Dealer.
Contact Dealer.
Contact Dealer.
Contact Dealer.
3.10.3 Climate Controls, page 60
and
Revision A