Forum Discussion
ExTreker_Vic
Mar 03, 2020Explorer
There are a couple of systems/methods used to control the temperature.
One uses a shut off valve that is operated by the temperature controller on the dash. The other uses a damper to mix the amount of outside air passing through the heater core.
Some are mechanically controlled and others use vacuum to control both the valve and the dampers.
The first step would be to determine which system you have and if it is working properly.
When changing from floor, to dash, to defrost, is the air flow coming out the correct vents?
How is the temperature controlled and is that working?
If all of the above is working the heater core may need to be flushed. This can be done with a garden hose. Disconnect the lines from the core. Connect the garden hose to the core so the flow is opposite direction to normal flow. Run the water through and reverse the lines and run the water again. Do it a couple of times.
Reconnect the lines.
Had a no heat issue with a Jeep. Went though all of the above. After flushing, had to turn the heat down otherwise it was unbearable.
One uses a shut off valve that is operated by the temperature controller on the dash. The other uses a damper to mix the amount of outside air passing through the heater core.
Some are mechanically controlled and others use vacuum to control both the valve and the dampers.
The first step would be to determine which system you have and if it is working properly.
When changing from floor, to dash, to defrost, is the air flow coming out the correct vents?
How is the temperature controlled and is that working?
If all of the above is working the heater core may need to be flushed. This can be done with a garden hose. Disconnect the lines from the core. Connect the garden hose to the core so the flow is opposite direction to normal flow. Run the water through and reverse the lines and run the water again. Do it a couple of times.
Reconnect the lines.
Had a no heat issue with a Jeep. Went though all of the above. After flushing, had to turn the heat down otherwise it was unbearable.
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