Q: Heater malfunction

asked by on July 27, 2016

I have an issue with the heating in my van. When the weather is cold, I would have normal heating in the vehicle. However, the heater would suddenly start blowing barely warm air out or even worse cold air. It would occasionally work normally. What could I do to fix this?

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Hello. There are several possible components that could be causing the problem you are having with your heat. If the thermostat is sticking intermittently or if the heater control regulator opens and closes when it isn’t supposed to, it could cause the heater to blow cold air. This regulator controls whether the air comes out hot or cold.

The heater control valve is operated electronically and intermittent problems may occur if the heater control valve circuitry is bad. If the heater core is clogged this may also cause cold air to blow instead of hot air. Have a certified technician, like one from YourMechanic, come and inspect your vehicle in order to determine why your heater is not working and make the necessary repairs.

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