How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Brian HVAC Guy Your Own Question
Brian HVAC Guy
Brian HVAC Guy, HVAC Technician
Category: HVAC
Satisfied Customers: 852
Experience:  I have been an HVAC/R mechanic/technician for 30+ years.
67988511
Type Your HVAC Question Here...
Brian HVAC Guy is online now
A new question is answered every 9 seconds

My carrier furnice fan continues to run after the

Customer Question

my carrier furnice fan continues to run after the temperature has been reached and the fan should go off, what part needs to be replaced
JA: I'll do all I can to help. How long have you been dealing with this?
Customer: just one day
JA: Do you plan on doing the work yourself?
Customer: yes if not to complicated
JA: Anything else we should know to help you best?
Customer: the model # is 518A042 AN OLDER UNIT, THE THERMOSTAT IS ALMOST NEW AND HAS BEEN WORKING FINE
JA: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat?
Customer: NOT IN THE THERMOSTAT, POSSIBLE A SENSOR OR SWITCH THAT DOES NOT SHUT DOWN THE FAN AFTER THE SET TEMPERATURE HAS BEEN REACHED
Submitted: 2 months ago.
Category: HVAC
Expert:  Brian HVAC Guy replied 2 months ago.

Hi I'm Brian and I'm here to help!

It sounds like you might have an older furnace with a "Fan & Limit control" type of fan and safety control. Many of these are adjustable and they get out of adjustment over time. It's possible you can adjust it if that's the issue. A picture of yours would help, Click Here for a picture of a typical fan and limit control.

The actual model number of your furnace would be helpful too. The number you gave is for the ac a-coil that sits on top of your furnace. Your furnace's model number will likely be behind the blower panel you have to remove it to see it.