When the heater only works on high, the most common problem is a blower motor resistor. The correct repair is to replace it with a new resistor.
Average mileage: 114,026 (30,000–200,000)
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My heater AC motor does not work on the lowest two settings.
My heater only worked on high before, and when I would turn it on it would make a horrible screeching sound. The thermostat turned out to be bad, once this was replaced, it seems to work a lot better.
my heater only works on the high setting, when i turn it on high it makes a loud noise and does not blow heat.
blower motor works on high only the resistor has been changed with no help, the temp. control panel has also been changed with no help what is next.
No heat unless I turn it to high
My low or high setting won't work
low does not work
Heat only works on high. Have not got it fixed as it was winter.
Had to replace my heater control unit because it only worked on high.
heat and air controls only work on low and high
The heater works on high only
heater only works on high