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 Phil Your Own Question
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 5648
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
Type Your HVAC Question Here...
Phil is online now
A new question is answered every 9 seconds

My daughter has the problem of the thermostat not light. There

Customer Question

My daughter has the problem of the thermostat not light. There is a switch on the stat to control the fan auto or mode. When she switches the fan to auto it does come on leading one to believe that in some sense the thermostat is functioning. It stopped working today after a power outage; my daughter changed the battery and also went to the breaker panel switching the designated switch off and on more than once and then used the master switch. No result the thermostat is not functional. it controls a heat pump. Sorry I have none of the specs or model numbers. I was inquiring online to see what I might find as she called me - we live more than 100 miles apart,
JA: Sometimes HVAC issues that that you think will be really complicated end up being easy to fix. The HVAC Technician I'm going to connect you with knows all the tricks and shortcuts. Anything else I can tell the HVAC Technician before I connect you two?
Customer: No thanks!
JA: I'm sending you to a secure page on JustAnswer so you can place the $5 fully refundable deposit now. While you're filling out that form, I'll tell the HVAC Technician about your situation and connect you two.
Submitted: 6 months ago.
Category: HVAC
Expert:  Airheatman replied 6 months ago.
Tell me exactly what is happening. What do you mean by thermostat not light?
Customer: replied 6 months ago.
Was lighting showing temp, mode etc. not lighting or functioning. No display lighted or visible - was lighted & visible earlier. That is why she tried changing batteries/switching breakers. Stat appears to be "dead" - non-functional. There was a large power interruption the same day - power went out in house. Power returned & all else is functional in house except stat. Is that clearer?
Expert:  Airheatman replied 6 months ago.
Yes, Thanks. Now you say that on auto the fan work, right? And does heat or ac work?
Customer: replied 6 months ago.
No! No heat/AC
Expert:  Airheatman replied 6 months ago.
OK very likely thermostat is not getting power from furnace or it could have taken a power spike.Does she have a volt meter to do some troubleshooting as I guide?
Customer: replied 6 months ago.
Don't think so but seems logical that perhaps a spike wiped it out as it was functioning earlier in day. Is it possible the fan auto switch could be operable if the stat is blown tho?
Expert:  Airheatman replied 6 months ago.
Yes, thermostat could be allowing a voltage bleed to tell fan to come on.If she wants to run to Walmart and pick up a meter or another thermostat,I will be happy to guide in troubleshooting or replacing.
Customer: replied 6 months ago.
That's a great idea. I will be going there two days from now. How could I reconnect with you Saturday afternoon day & receive your guidance?
Expert:  Airheatman replied 6 months ago.
After rating answer you can follow up for 30days at no additional costs by just going to "My Questions"

Related HVAC Questions