With the engine running at full temp jack the front of the car up and let it run for 2 minutes then go to the rear of the car and do the same thing, this will burp or purge the air bubbles locked in the heater core and allow the heater to work again.
What would cause a car heater to stop working?
Causes of a breakdown
A heater can stop working for a number of reasons, including: A low antifreeze/water level in the radiator due to a leak in the cooling system. A bad thermostat that isn’t allowing the engine to properly warm up. A blower fan that isn’t working properly.
Why is the heater blowing cold air?
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. … If the pilot light isn’t lit, then the furnace’s burners won’t light, meaning no heat.
How do you diagnose a heater problem?
Method 1 of 4: Check proper fluid levels
- Materials Needed.
- Step 1: Verify radiator coolant levels. …
- Step 2: Verify reservoir bottle fluid levels. …
- Step 1: Turn on the engine. …
- Step 2: Check the temperature change on the dashboard. …
- Step 1: Locate the fan vents. …
- Step 2: Check for a broken or faulty fuse.
What do I do if my heater is blowing cold air?
When your furnace blows cold air, try turning the heating unit off and on. If the air feels warm for a moment or two, then switches to cold, it may be that the flame sensor is dirty. With a dirty flame sensor, your gas burner won’t stay lit, causing the air to go cold soon after the furnace turns on.
Why is my car not blowing cold air?
The most common causes of broken air conditioning are leaks or compressor issues. If your air is blowing cool but not cold, the problem could be a clogged filter, cooling fan problem, radiator trouble, or it could simply be that you need to recharge your AC.
Why does the heat in my car only work when Im driving?
The most common cause is allowing the coolant level to get too low. Some healthy engines need more regular coolant top-ups than others. Allowing the coolant to get too low causes air to enter the system and for most just topping up the coolant causes the air to leave the system but for some, it needs some help.
Why is my heater not blowing hot air?
The Furnace Is Blowing Cold 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.
Would low coolant cause no heat?
First, check your coolant level to be sure there is enough liquid in there to even get to your heater core. If your radiator is very low on coolant, you’ll get no heat. If your levels are okay, you either have a bad water pump or a thermostat that isn’t opening.
Why is my heater not reaching set temperature?
What Causes Thermostat Not Reaching Set Temperature Problems? … The thermostat is in a location that is not optimal. Your air conditioner or furnace itself is having a problem. Dirty ducts or vents are causing airflow issues.
How do I reset my thermostat?
Here are the step-by-step reset instructions:
- Turn your thermostat off by switching it to the off position.
- Find the breaker that powers your HVAC system and turn it off.
- Wait 30 seconds and turn the breaker back on.
- Turn your thermostat back on.
Why is my car blowing hot air on one side and cold on the other?
Blend door actuators are the most common reason for the car air conditioning to blow cold air on one side and hot air on the other. They can be diagnosed with an advanced scan tool. … If it does not move with the adjustments and commands, there is a problem with the blend door actuator and it will need to be replaced.
How can I test my car heater?
How to Test a Heater Core
- Turn the engine on, and see if the heater works inside the car. …
- Check the radiator for coolant and the thermostat for correct operation. …
- Smell the flow of air from the defrost vents after the engine has been running for a minute or two.
What to do if the heater is not working?
Heater Not Working? 7 Troubleshooting Tips:
- Check that your thermostat is set to “heat.” …
- Change the filter. …
- Make sure the gas is on. …
- Clear the chimney exhaust flue. …
- Clean away leaves and debris from exhaust vents. …
- Flush out the drain lines. …
- Check for blocked ducts restricting airflow.