AC compressor always runs

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Sep 27, 2005 | 11:39 AM

phantmlord

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AC compressor always runs

Hi,
I have a 1995 ford conversion van with a 5.8 L engine. It seems my ac compressor is always running, even when I have the heat on. This causes my heater to blow warm air at best. Before I start replacing a bunch of parts, I thought someone might know the answer. I was thinking a faulty heater control unit in the dash.
Thanks,
Brian

Sep 27, 2005 | 03:36 PM

phantmlord

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My AC compressor runs when the heat is set to vent, floor, defrost or when the AC setting is on. It does not run if the heater control unit is turned off.

Sep 28, 2005 | 09:37 AM

goofy173

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From: Northern Indiana

I guess I start first by pulling the plug on the low-pressure cut-out switch and see if it continues to run. If it does, it's not a controller problem.

I don't know your expertise so I have to ask, how do you know it's running?

Sep 28, 2005 | 11:02 AM

phantmlord

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my van hasn't had real heat for some time. Recently, the metal line that runs to the rear heater core sprung a leak. After I replaced the line, I was doing a flush and fill and noticed that on defrost, with the heat at max setting, the compressor was still kicking on. So I checked other settings as well and found that the compressor kicks on at every setting.

Sep 28, 2005 | 12:01 PM

Bear River

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From: Salt Lake City, Utah

Other Fords do this too, but that does not mean that the compressor is actually cooling the air through your vents. The blender door prevents chilled air from entering the vents. The continueous cycleing prevents problems with the AC system, namely seals drying up and leaking the refrigerant out. It is very annoying, so I suggest you simply unplug the wire that leads to the compressor clutch , or attach an inline switch. I suggest adding a new switch to the dash, and label it AC. When the switch is turned on, the compressor will cycle regardless of temperature setting. When it is off, the compressor cannot cycle. This way, you can control the compressor, and cycle it easily a few times per winter.

Sep 28, 2005 | 11:53 PM

pfogle

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From: Oak Harbor, OH

It should only run when in DEFROST or A/C mode. The dry cool air will help in defoggin the windows. If it's running all the time I'd suspect the control swtich in the dash.

Sep 29, 2005 | 11:14 AM

Bear River

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From: Salt Lake City, Utah

We have a 1997 Ford Ranger, and it runs whenever the setting is anything other than vent or off. I guess that is the same as what you just said, but it should cycle throughout the year to extend the systems life, and prevent the seals from drying out. Just disable it by either just unplugging it, or installing a switch. I suggest the switch, so that you can easily cycle it manually.