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Rick, HVAC Supervisor
Category: HVAC
Satisfied Customers: 21177
Experience:  40+ yrs. experience as a licensed oil & gas technician.
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My trane furnace turns on, but the fan doesn't kick on, and

Customer Question

my trane furnace turns on, but the fan doesn't kick on, and then i get the four fast flashing open high limit
JA: Did you check the furnace's filters?
Customer: yes i just changed one
JA: Do you plan on doing the work yourself?
Customer: i will try
JA: Anything else we should know to help you best?
Customer: i don't think so
Submitted: 5 months ago.
Category: HVAC
Expert:  Rick replied 5 months ago.

Welcome to Just Answer, my name is ***** ***** I will do my best to help you with your issue. If my initial response doesn’t answer your question then let me know and we can continue our conversation.

You probably have either a bad blower motor or a bad start capacitor. You need to test the voltage to the blower motor after the burners fire up to confirm this.

Customer: replied 5 months ago.
i have a multimeter, but i don't know how to use it or where to test. Either one of those problems would require a real technician to be here to fix right?
Expert:  Rick replied 5 months ago.

Most likely it's best to call in a pro for this given your description.

Customer: replied 5 months ago.
this is already going to cost me a fortune, so i would rather just chat to see if its something i can fix
Expert:  Rick replied 5 months ago.

If you don't know how to use the meter then you can't verify the culprit. The call prompt is automatic. I have nothing to do with it

Expert:  Rick replied 5 months ago.

The other (less likely) possibility is a bad fan control. You need to do some voltage testing to confirm which one is the culprit. I have been called away. I should be back in less than an hour. I'll respond when I get back if you have more questions.