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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have an e23 code on my Nest and no heat and it is -25

Customer Question

Customer: ***** ***** and I have an e23 code on my Nest and no heat and it is -25 outside
JA: Thanks. Can you give me any more details about your issue?
Customer: It was working fine about an hour ago
JA: OK got it. Last thing — HVAC Technicians generally expect a deposit of about $18 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.
Category: HVAC
Expert:  airheatman replied 1 year ago.

The E23 indicates the NEST is not getting 24v from furnace.

1.Do you have a meter for troubleshooting?

2.Is this a new installation?

3.What is model on indoor unit?

4.What wires do you have at the Nest and to what terminals?