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I have a Honeywell th9421c004 with a blank screen. A few…

Customer Question
I have a Honeywell...

I have a Honeywell th9421c004 with a blank screen.

Contractor's Assistant: I'll do all I can to help. How long have you been dealing with this?

A few days. We removed it to paint the walls and when we put it back it was blank

Contractor's Assistant: Do you plan on doing the work yourself?

Yes.

Contractor's Assistant: Anything else we should know to help you best?

Is there a fuse I can replace? If so where is it?

Submitted: 2 months ago.Category: HVAC
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Answered in 45 minutes by:
5/28/2018
HVAC Technician: airheatman, HVAC Technician replied 2 months ago
airheatman
airheatman, HVAC Technician
Category: HVAC
Satisfied Customers: 9,367
Experience: Furnace, A/C and heat pump specialist.
Verified

If you did not turn off power at furnace you probably blew a fuse in furnace by allowing wires to touch. Look inside furnace and check fuse on board.

https://i.imgur.com/kYe4Epz.png

https://i.imgur.com/UxPpnn4.png

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Customer reply replied 2 months ago
Yep. It was locating the fuse that was difficult. Not sure why there isnt an easier access hatch for something with a high failure rate.
HVAC Technician: airheatman, HVAC Technician replied 2 months ago

If you have further questions, please let me know.
Thanks for letting me work with you.When we are finished if my answer has been polite, professional,and thorough, please click one of the ratings before you go. If you still need help let me know!.Expert is not paid for assisting you until you rate answer.Feel free to follow up for 30 days at no additional cost. Bonus always appreciated if you feel justified.
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Customer reply replied 2 months ago
Now the thermostat is showing Err 89
Customer reply replied 2 months ago
Any ideas?
HVAC Technician: airheatman, HVAC Technician replied 2 months ago

Usually heating /cooling equipment missing.Try turning power off and back on to equipment

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Customer reply replied 2 months ago
I've cycled the breakers it came up for a while now tge error code is back.
HVAC Technician: airheatman, HVAC Technician replied 2 months ago

Are you sure all wiring is as it was.

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Customer reply replied 2 months ago
Nothing has changed.
HVAC Technician: airheatman, HVAC Technician replied 2 months ago

HMm, mIght have to get an onsite tech in on this one.

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