From https://www.justanswer.com/ythi
JustAnswer Customer: I got an e24 error code on my nest thermostat.
JustAnswer Customer: No power to the rh wire.
JustAnswer Customer: I took panels off of my furnace to locate any type of fuse but no luck.
JustAnswer Customer: I don't even see the circuit board.
JustAnswer Customer: Furnace is old too
Pearl Wilson: Assistant: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat?
JustAnswer Customer: More than likely something specific to thermostat
Pearl Wilson: Assistant: Do you plan on doing the work yourself?
JustAnswer Customer: I'm trying to see If i have a blown fuse on the furnace.
JustAnswer Customer: But yes I plan on doing it myself
Pearl Wilson: Assistant: Anything else we should know to help you best?
JustAnswer Customer: I just replaced the fan motor and capacitor on the ac outside.
JustAnswer Customer: That was 3 weeks ago.
JustAnswer Customer: Been working perfect ever since.
JustAnswer Customer: Up until 2 days ago.
JustAnswer Customer: I don't know if they're related.
JustAnswer Customer: I doubt it
Regan Land: HVAC Technician: Hello and welcome to Just Answer - My name is * * I'll be happy to assist you today.
Regan Land: HVAC Technician: Can you remove the face of the nest to expose the wiring?
Regan Land: HVAC Technician: Make sure the panels on the furnace are back on (so that door switch is pushed in) and remove the red wire from Rh and green wire from G and touch (and hold) the wires together.
Regan Land: HVAC Technician: Does the indoor fan come on?
JustAnswer Customer: I'm at work at the moment.
JustAnswer Customer: I can when I get home
Regan Land: HVAC Technician: Okay, sounds good - Just post your findings here and I'll be alerted.
JustAnswer Customer: Ok thank you
Regan Land: HVAC Technician: No problem - talk to you soon
JustAnswer Customer: I just used a jumper wire to the rh wire and g wire.
JustAnswer Customer: Fan came on
JustAnswer Customer: Jumped red wire to green wire and fan came on instantly
Regan Land: HVAC Technician: Uh oh, that means the thermostat is getting power to the Rh terminal, which, unfortunately, would indicate that the Nest is bad.
Regan Land: HVAC Technician: How old is your thermostat?
Regan Land: HVAC Technician: Nest has a 2-year limited factory warranty, and adds an additional 3 years if it was purchased and installed by a Nest Pro dealer.
JustAnswer Customer: I just bought the house 2 months ago
JustAnswer Customer: Not sure how to figure out how old it is
Regan Land: HVAC Technician: You can contact Nest and provide the serial #.
Regan Land: HVAC Technician: If it was manufactured or if they have a sell date in the system that is within 2 years then they should cover it under warranty.
JustAnswer Customer: Ok thank you very much man
Regan Land: HVAC Technician: No problem - I wish we could've fixed it for you.
Regan Land: HVAC Technician: When it comes time to replace it, be sure to turn the power to the indoor unit off prior to removing existing wires.
Regan Land: HVAC Technician: If all is good and you're happy with my services, could you do me a favor and rate me?
Regan Land: HVAC Technician: It would be much appreciated.
Regan Land: HVAC Technician: Thank you for using Just Answer!
JustAnswer Customer: I troubleshot this with a tech from nest and found out there is no power coming from the ac to the thermostat.
JustAnswer Customer: That's why there's an issue.
JustAnswer Customer: When I unplug yellow wire from y1.
JustAnswer Customer: Everything registers fine except I have no ac.
JustAnswer Customer: 3 weeks ago.
JustAnswer Customer: We put in a new ac fan motor.
JustAnswer Customer: With a different used capacitor.
JustAnswer Customer: Has been working fine since this dilemma.
JustAnswer Customer: Any suggestions?
Regan Land: HVAC Technician: The Nest tech is incorrect - There is power to the thermostat.
Regan Land: HVAC Technician: Power comes through the red wire to Rh.
Regan Land: HVAC Technician: When we jumped Rh to G and the fan came on that verified that there is power through the red wire.
Regan Land: HVAC Technician: There is an internal problem with the Nest board - unless there's high voltage power going through the yellow wire.
Regan Land: HVAC Technician: do you have a volt meter by chance?6
JustAnswer Customer: No I don't.
JustAnswer Customer: When I unplugged yellow wire to y1.
JustAnswer Customer: I have no codes and I can turn on the fan through the thermostat.
JustAnswer Customer: This is a 5 year old nest 2nd gen.
JustAnswer Customer: I will take your word.
JustAnswer Customer: If you think I should get a new thermostat.
JustAnswer Customer: What would cause no power from ac that I can look into before i go this route?
JustAnswer Customer: I can acquire a volt meter.
JustAnswer Customer: What should the yellow read?