MacDon M155 2022 - Cab Air Troubleshooting

215676 455 Revision A
6.7 Cab Air Troubleshooting
Refer to the table provided below if you encounter problems with the cab air system while operating the windrower.
Problem Solution Reference
Symptom: Blower fan will not run
Burned out motor Contact Dealer. Contact Dealer
Burned out switch Contact Dealer. Contact Dealer
Motor shaft tight or bearings worn
Contact Dealer. Contact Dealer
Faulty wiring—loose or broken
Contact Dealer. Contact Dealer
Blower rotors in contact with housing
Contact Dealer. Contact Dealer
Symptom: Blower fan operating but no air coming into cab
Dirty fresh air filter
Clean fresh air filter.
Inspecting and Cleaning
Fresh Air Intake Filter
Element, page 335
Dirty recirculating air filter Clean recirculating filter.
Cleaning Return Air
Cleaner/Filter, page 337
Evaporator clogged Clean evaporator.
Cleaning Air Conditioning
Evaporator Core, page
339
Air flow passage blocked Remove blockage.
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Symptom: Heater not heating
Heater shut-off valve at engine closed
Open valve.
3.10.1 Heater Shut-Off,
page 53
Defective thermostat in engine water outlet manifold Replace thermostat.
Contact Dealer
Heater temperature control defective Replace control.
Contact Dealer
No thermostat in engine water outlet manifold
Install thermostat. Contact Dealer
Symptom: Odor from air louvers
Plugged drainage hose
Blow out hose with
compressed air.
—
Dirty filters
Clean filters.
Cleaning Return Air
Cleaner/Filter, page 337
Symptom: Air conditioning cools intermittently
Unit icing up – thermostat set too low Adjust thermostat.
Contact Dealer
Unit icing up – excessive moisture in system
Contact Dealer. Contact Dealer
Unit icing up – incorrect super-heat adjustment in the
expansion valve
Contact Dealer. Contact Dealer
Thermostat defective
Contact Dealer. Contact Dealer
Defective blower switch or blower motor
Contact Dealer. Contact Dealer
Partially open connection, improper ground or loose
connection in compressor clutch coil
Contact Dealer. Contact Dealer
Compressor clutch slipping
Contact Dealer. Contact Dealer
Symptom: Air conditioning not cooling
Low refrigerant level Add refrigerant. Contact Dealer.
Contact Dealer
Clutch coil burned out or disconnected Contact Dealer. Contact Dealer
Blower motor disconnected or burned out Contact Dealer. Contact Dealer
TROUBLESHOOTING