Heater and Air Conditioning System

If	Check
All cab electrical switches do not work	Loose, defective or blown fusible link. See your John Deere dealer.
Blower malfunctioning	Blown fuses. Blower does not work. See your John Deere dealer.
Blower operates only in high position	One of two fuses blown. Blown blower resistance assembly. See your John Deere dealer.
Heater does not work	Low coolant level. Check coolant level; add if necessary. Faulty thermostat. See your John Deere dealer. Heater control valve not functioning properly. See your John Deere dealer. Heater core or hoses clogged or damaged. Flush cooling system. See your John Deere dealer. Replace heater core or hoses. See your John Deere dealer.
Air conditioning does not work	Blown fuse. Faulty wiring or loose connections. Fan belt loose or slipping. Defective switch. See your John Deere dealer. Defective compressor clutch. See your John Deere dealer.
Drafts	Poor air distribution. Adjust directional air louvers. Set blower switch to medium or low positions.
Inadequate air flow	Clogged air filters. Evaporator core air flow restricted. Faulty blower fan motors. See your John Deere dealer. Defective blower switch. See your John Deere dealer. Faulty wiring or loose connections.
Water leaking or dripping from evaporator core compartment	Loose hose clamp. Evaporator condenser pan dirty. A/C drain tubes plugged.
Strange odors inside operator’s cab	Dirty air filters. Evaporator condenser pan dirty. A/C drain tubes plugged. Tobacco smoke and tar on evaporator exterior.
Partial frosting and sweating of lines combined with poor cooling	Fan belt slipping. Loss of refrigerant. See your John Deere dealer. Restricted or clogged liquid line. See your John Deere dealer Expansion valve malfunctioning. See your John Deere dealer.
Ice flecks blowing from evaporator	Control dial set too low. Adjust temperature control to a warmer position.
Failure to cool	Insufficient blower speed. Dirty air filters. Debris on front grille. Lint or dirt on condenser fins. Refrigerant is lost or extremely low. See your John Deere dealer. Loose fan belt. Compressor clutch not engaging. See your John Deere dealer. Expansion valve not functioning. See your John Deere dealer. Restriction in refrigerant system. See your John Deere dealer. Faulty wiring or loose connections. Defective temperature control switch. See your John Deere dealer. Outside temperature too low, below 21? C (70? F). Wait until day gets warmer. If there is a malfunction in system, see your John Deere dealer. Condenser is overheating. Clean condenser screens, cores and fins of condenser and radiator. Severe restriction in high side. See your John Deere dealer. Burned out clutch field or faulty field. See your John Deere dealer. Short circuit in control circuit or failure of a switch in circuit. See your John Deere dealer.
Hissing noise at expansion valve	Loss of refrigerant. See your John Deere dealer. Restriction in refrigerant system. Check receiver-dryer for uniformity of temperature. See your John Deere dealer.