Why is my heat not blowing warm air?

Why is my heat not blowing warm air?

First, check to make sure the thermostat is set correctly. You will want to make sure that the fan control is set to auto, and not ‘on’. If the thermostat appears set correctly, turn off your heater at the thermostat and check the filter. If the filter is dirty, replace it.

Why is my thermostat on but no heat?

A clogged filter is probably the most common reason for this problem, so it’s a good place to start investigating. Take a look at your filter and, if it’s really dirty and clogged, it means there’s restricted airflow to your furnace. This may be keeping it from being able to create heat.

Would a blown head gasket cause no heat?

A blown head gasket can keep your car from starting. When you have a blown head gasket, you may have no heat, no white smoke, no start, no check engine light, or even no overheating in some cases.

How do I know if my heater is not working?

What to Check First If Your Heater Isn’t Working

  1. Check the Furnace Power Switch. Some furnaces have an on/off switch that is frustratingly easy to switch off by mistake.
  2. Look at Your Fuse Box That Powers Your Heater.
  3. Check the Batteries in Your Thermostat.
  4. Replace the Air Filters.
  5. Notice Any Odors.
  6. Heater Isn’t Working?

What causes a car heater to have no heat?

Low coolant will result in low heat or no heat. If low, add coolant. Next, check the hoses to the heater core when the engine is hot. Both the incoming and outgoing hoses should be HOT. If one hose is hot and the other cold, you’ve got a clogged heater core, a restriction in the system or air in the system.

What can I do about my 2000 GMC Sierra heater?

I have a 2000 hmm siarra . Having a problem with it it is stuck on the defrost vent and only blowing hot air . I had the a/c checked out . They said it was fine working good ,and no leeks . They said my hvac control box was bad . I changed it but still the same thing ? What can it be . 2 people found this helpful.

What to do if your heater is not working?

Remove the COP bolt and Remove the COP. Remove any foreign debris from the spark plug wells with compressed air. Remove the spark plugs. To install, reverse removal procedure. Tighten to specification 7-14 ft lbs. Make absolutely sure to do on a COLD engine and use anti seize on replacement plugs.

What to do if your heater is blowing cold air?

Coolant level: If your coolant level is low, your heater core may not be getting enough warmed coolant through it to produce adequate heat. Solution: Top up the coolant and see if it helps. If the level is low due to a leak, track down the source and get it repaired.