a/c Compressor Q's

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Nov 26, 2007 | 06:54 PM

03_PSD

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a/c Compressor Q's

I'm about to beat this to death. I'm still dealing with no heat. So far what I've done is change to the 203* stat and billet housing, still no heat. I have felt the heater hoses and they are hot, were hot before the stat change. One thing I have noticed is that the a/c comperssor runs all the time, even when just on vent. Don't really know what else to check. Seems I'm always turning wrenches now, but well worth it when I can save some money.

Nov 26, 2007 | 07:36 PM

F350-6

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From: Texas

I'll have to check mine tomorrow if no one else chimes in. I know the compressor will run on vent when it's pointed toward the cold side, but I thought it shut off at some point on the hot side.

Thermostats and housings should not affect operation of the heater. Do you get warm air or just outside temperature air? To me it sounds like you have an issue with your switch. Have you checked the heater core (behind the glove box) to see if your getting hot fluid through there?

Nov 26, 2007 | 08:02 PM

03_PSD

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the a/c compressor does not cut off when switch is on heat. there is no heat at all....compressor runs continuously whether the switch is on cold or hot, always cold air comming through the vents. i'll have to check the heater core tomorrow. what should i look for on the heater core, see if its warm?

Nov 26, 2007 | 08:08 PM

medhvac

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From: house springs,mo

unplug your compressor and see if the heat works then!

Nov 26, 2007 | 08:12 PM

F350-6

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Yes, the heater core is basically like a mini radiator. The hot coolant is pumped through it and air is blown accross the coils to provide heat. You could probably check it from the engine compartment too. There will be 2 rubber hoses approximately 1" diameter going to the heater. One is supply, the other is return. If both of them are hot after the truck warms up I'd say you have a switch (****) issue.

I'll check tomorrow if my compressor runs at max heat on vent setting.

Nov 26, 2007 | 08:39 PM

03_PSD

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i thought i saw one another thread that there is a switch or door that opens and closes to allow heat or cold to pass. how can you tell if that is bad or is it the switch that tells it whether to open or close. i think it is called a door blend or something???

i'll try to unplug the compressor and see about that but wouldn't the air seem somewhat warm even if the compressor was still on when switched to heat. right now cold air is comming out no matter which position the switch is in.