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Problem My Gas Furnace Will Not Heat! What Furnace Parts Might Cause This Problem?

Problem: My Gas furnace will not heat or work. What furnace parts might be the cause of this problem? 

Answer: We have this question asked lots. There are 6 main parts that can cause your furnace to not heat. Some of these parts can be blamed or misdiagnosed as bad when actually the part is good. The only way to find out if the part is bad or not is to do some testing. Below we have a really good super YouTube video where AC Service Tech LLC shows and explains what the 6 most frequently misdiagnosed parts are and how to test them. I have listed below the video many troubleshooting links where AC Service Tech explains how to troubleshoot each furnace part in detail. There are also links to the troubleshooting tools that AC Service Tech uses in the video. Thanks so very much to AC Service Tech LLC. for making these excellent informative videos!! 

The 6 parts that are blamed and misdiagnosed most often are:

  1. Flame Rod or Flame Sensor- Usually cleaning the flame sensor will fix the problem.
  2. Gas Valve –AC Service Tech LLC has testing and troubleshooting links to YouTube Videos below.
  3. Pressure Switch-AC Service Tech LLC has testing and troubleshooting links to YouTube Videos below.
  4. Control Board-AC Service Tech LLC has testing and troubleshooting links to YouTube Videos below.
  5. Blower Motor is bad or on High-Efficiency furnaces, the ECM Blower Motor is diagnosed as bad-Many times a motor run capacitor can be replaced on PSC (Permanent Split Capacitor) blower motors and it will fix the blower motor problem. Most of the time the ECM motor module is bad and the motor is not actually bad. Replacing the motor module is less expensive than replacing the entire ECM motor.  AC Service Tech LLC has testing and troubleshooting links to YouTube Videos below.
  6. Heat Exchanger is bad. If one of your rollout switches is going off where you have to reset the rollout switch then this is a sure sign that you have a heat exchanger or venting problems. Make sure your condensate drain is open and your vent is not obstructed if you have a 92% or above condensing furnace that produces water during the winter.

Below we have a great video made by AC Service Tech LLC. that shows the

Below are many links to a more detailed explanation for troubleshooting the problems described in the video. Thanks so very much AC Service Tech LLC. 

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