Why is my furnace blowing cold air instead of heat?

Why is my furnace blowing cold air instead of heat?

Your furnace may be blowing cold air because the filter is too dirty. A dirty air filter blocks airflow over the furnace’s heat exchanger, causing it to overheat. When overheating, your furnace can trip a high limit switch, causing the furnace burners to shut off so that the heat exchanger does not crack.

Why is my thermostat not working?

Try replacing the batteries, then check for a blown fuse or tripped breaker in the electrical panel. If the thermostat is still unresponsive, make sure the breaker is shut off and remove the cover. If the wiring looks corroded, consider replacing the thermostat.

How do you know if your heating thermostat is broken?

The most common signs of a broken thermostat are:

  1. Thermostat display is off or is non-responsive.
  2. Turning on the heat or AC does nothing.
  3. The heat or AC will come on, but either stays on nonstop or cuts out before the temperature setting is reached.

What causes a heater to blow cold air?

The following are some issues that may be causing the heater to blow cold air: Low coolant levels. A plugged/clogged heater core. A faulty thermostat (thermostat that is stuck) Broken blower and/or blower motor. Heater core bypass hoses that have leaks.

What happens if my heat pump fan is not working?

One purpose of the fan is to cool the compressor. With the heat pump fan not working, the compressor can overheat and be damaged – and that will increase your repair bill by $1,250 to $2,000 plus. If that happens, your heat pump might be “totaled.”

Why does my car fan keep blowing cold air?

Engine fan: Most vehicles today have a thermostatically controlled electric fan that comes on when additional engine cooling is necessary. A defective thermostatic switch could make the fan run continuously, reducing the coolant temperature to the point where you can’t get enough heat into the interior.

Why is my AC not working but fan is running?

In most cases, if the AC is not working, the root of the problem often traces back to the HVAC compressor. The heat of summer can be intense, and the worst thing that can happen is finding yourself with a malfunctioning HVAC compressor. A working AC will provide you with nice and cold air as opposed to bearing the brunt of warm, dry air.