AC instead of heat

[purg113]

I turn the heater on to anything but floor and the ac turns on so i have the ac pump/clutch keeps turning on yes I have it set to heat not ac.

 

[purg113]

Can anyone tell me what might be causing this it is cold hear so i need my heater

 

[lindstromjd]

Probably a bad selector. You can always just unplug the wires that go to your a/c compressor for now... it won't hurt anything.

 

[Matrix37495]

Im a defrost setting the compressor is supposed to come on to help "dry" the air. On my 93 I noticed the compressor engage kind of like yours but it had no trouble heating up the cab.

Unplug the clutch and see if you have heat then. If not check the little bypass on the heater hoses and make sure hot coolant is reaching the core...

 

[bab029]

Could also be the blend door stuck/ a vacuum line broken. Look under hood on passenger side near where the heater core hoses pass through the firewall. There's a little canister with an actuator arm coming out that is vacuum operated. This controls the blend door.

 

[purg113]

Okay I will look at that blend door in the morning and I have the ac unpluged right now and it heats but not real well

 

[John Deere]

I second the blend door, also check your coolant level, a significantly low level will cause no cab heat.

 

[sassyrel]

purg,,,,have a tendency,,to leave pencils,,and other small items,,stacked on your dash???? if those fall down,,into the duct area,, and get caught in the blend door,,bye bye blend door,,as the hinge is plastic,,and the vacuum diaphragm has enough power to pull the door,,and break the hinges..removal of heat box to replace is necessary..