Ask Me Help Desk - Heater doesn't stay on

My heater is sort of broken. When I turn the thermostat on what it usually does is the heater will make the sound of it getting ready to pump out hot air for a few minutes then the blower will turn on. It heats up the house for a minute or two then turns off and goes back to making the sound of getting ready to pump out more heat. The blower will turn on the 2nd time and then turns off and makes that sound again. On the 3rd time it will do one of two things: 1) It will rarely turn on and heat the house to the temperature that I set the thermostat too, or 2) It will turn off then make that sound again but no matter how long I wait the blower won't turn back on until I turn the thermostat to off then back on.

So long story short, it will turn on and blow out heat 3 times. After the 3rd time it will either shut off or heat up the house. Any ideas what my problem could be? Really appreciate any help.

Sounds like the blower relay is bad. Unfortunately it is beyond most DIY to diagnose and replace one short of a new circuit board, $$$$$$$$. Even if you call a technician, likely he will replace the board adding $100 labor. If you look at the heating and cooling forum, you will see many similar questions and answers. I wish I had a better fix.

Quote:

Originally Posted by Soccergodgt

My heater is sort of broken. When I turn the thermostat on what it usually does is the heater will make the sound of it getting ready to pump out hot air for a few minutes then the blower will turn on. It heats up the house for a minute or two then turns off and goes back to making the sound of getting ready to pump out more heat. The blower will turn on the 2nd time and then turns off and makes that sound again. On the 3rd time it will do one of two things: 1) It will rarely turn on and heat the house to the temperature that I set the thermostat too, or 2) It will turn off then make that sound again but no matter how long I wait the blower wont turn back on until I turn the thermostat to off then back on.

So long story short, it will turn on and blow out heat 3 times. After the 3rd time it will either shut off or heat up the house. Any ideas what my problem could be? Really appreciate any help.

A possible cause is over temperature (called limiting out) Check your air filter, or any other restrictions in the duct work. Are all your registers open? Inside the furnace the manufacturer will state the temperature rise (lets say 40-65 degrees) Record the temperature of the return air and the temperature of the supply air. Subtract return temp' from supply temp' and see if it is not to great. If you have had bad maintenance practices the main limit my be fatigued or weakened and will need to be replaced. The brand and age of the furnace would also be helpful to know. Modern furnaces for the most part will try to ignite 3 times, if it keeps sensing a problem the P.C. board will go into lock-out, alerting you to a problem.