Jaybird81
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1981 C10 A/C works but heater does not. Climate control unit is new. Where do I start?
A/C but no heat
- Thread starter Jaybird81
- Start date
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mattsk8
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I assume the blower is working when it's set to heat since you said the AC works? I would first check the coolant level. If coolant is full and temp on your temp gauge is good, possibly a plugged heater core.
fast 99
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are heater hoses hot, temperature difference between the 2? Temp split around 20-25 degrees indicates a plugged core, no or low flow. Check after warm and heater has been operating. When coolant was added did you bleed air out?
Jaybird81
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3/4 of a gallon low on coolant. See if that helps…
Jaybird81
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So I’m checking the routing of the hoses. And I think they are on backwards the top hose coming out of the firewall from the heater core should go to the radiator and the bottom hose coming out of the firewall should go to the engine, correct? Mine are the opposite.
Steelbuddha
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The heater core isn't directional, so which hose is on the top and which is on the bottom shouldn't make any difference as long as there's coolant flowing through it. (Which it sounds like there might not be.)
Laqota
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Make sure your HVAC ball is hooked up to a vacuum source. It should be on the passenger side next to the A/C box. Ignore anything anyone says about a check valve for it, ricko for example, it has one built in.
It's what comes through the firewall, to the vacuum splitter (Controlled by the settings lever on A/C controls) and moves the doors. it's not electronic like the new ones.
It's what comes through the firewall, to the vacuum splitter (Controlled by the settings lever on A/C controls) and moves the doors. it's not electronic like the new ones.
