When my heater controls are in the defrost or combination modes the ac compressor is constantly going on and off. Is this normal? It stays on continuously when it is in the ac mode.

Budman

 

Define "constantly" Do you mean like every second, or every minute or what? I was under the impression that the compressor is activated only when in "defrost", or "a/c", or "max"

Mine kicks on and off periodically. It's according to outside temp. as to how often it does it.

 

Sorry for not being specific. It would switch on about every minute or minute and a half. And it would only stay on for about that much time. It seemed odd I thought it only was supposed to come on in the ac or defrost mode. It does this in the combination modes but not in the floor mode.

Budman

 

I think it's fine. Mine does that too. I don't think the compressor even turns on in the floor mode. Only A/C and defrost. See, in order for the air to "defrost" the windshield, it has to have a low humidity. When you turn the controls to "defrost" it activates the compressor, which dries the air out, and then blows it onto the windshield in an effort to defog the windshield. Even in a combonation mode, the compressor is still running. It's a way of keeping the relative humidity of the truck down and preventing condensation.

I always leave my controls set on A/C max. Even in the winter. I just turn up the heat a little bit.

When your truck is in "max" it draws air from inside the cab instead of from outside. It helps keep dust, smoke, dead animal smell, etc.. out, and it keeps all my windows from fogging up by keeping the humidity low.

 

Thanks for the reply. This forum is great. Every question I have someone on here has the answer.

Budman

 

Normal operation.

AC compressor operation is enabled in every mode except OFF, FLOOR, and VENT. Once enabled, actual compressor operation is dependent on system pressures, temps, AC loads, and engine operating conditions.

This information is in your owner's manual. If you don't have one in your glovebox anymore, you can download a copy from various official Ford sites including www.fleet.ford.com

Steve