Google Nest No Power Suddenly - Wire Issue

[nicolecandy44]

Hi everyone, 

My Google Nest suddenly stopped working and shows the error code "E298 No Power." It does not detect any of the Y-C-W-R wires. I have a weird hunch it has something to do with a new water heater I had installed because my furnace & heater are in the same closet. My Google Nest history shows it working up until the hour the plumbers arrived. I'm curious if anyone has had some kind of experience with this - potentially the plumbers turned off my furnace/gas/electric when they installed the water heater? I'm kind of at a loss, but I feel confident this is a problem that I can potentially solve without calling an expert to my place. Does anyone know if this sounds like a circuit breaker problem or if I actually need to call someone out here to check it out? Thanks in advance! 

[Todbone]

If your Nest isn't detecting any wiring and the furnace breaker and/or Emergency switch are both on, then the problem will most likely be in the low voltage wiring. Check the wire coming out of the furnace going to the thermostat. The plumber may have accidentally cut it somehow. Look through the site glass on the furnace door first and look for a solid or blinking red light. If it's blinking, count the short and long blinks, that will be the error code.

[CoolingWizard]

The nest thermostat receives approximately 24 Volts AC power from the furnace heating control board.  If the Plumber turned off the power to the furnace, he might have forgot to turn it back on.  Alternatively, he might have done something to short out the step down transformer and blower the control board fuse.  
Step 1. Confirm the Heating Air handler has power by checking the breaker and service disconnect. 
Step 2. If power is confirmed on, as stated by Todbone, see if there is an LED on or flashing at the air handler. 
Step 3 If the LED is on or flashing, you have power,  now check the thermostat cable coming out of the air handler. Is damaged by the plumber?

if you can find it, get me the Make and Model. Umber of your Furnace/Air handler.  I assume you have Gas Furnace?

Ken, The AC Cooling Wizard

[nicolecandy44]

Hi Ken and Todbone, thank you for your responses. I have a feeling something is wrong with my furnace because it is showing the error "1dL" or "idle"? I have a Goodman GM9S800603ANAA model. 

[CoolingWizard]

 Nicolecandy44 , that I DL stands that the system is currently ready and idle. Idle means it’s not receiving any call to either heat or cool or the blower to be just blowing. That is a normal status nothing to worry about. This also tells me that the 24 V transformer is working fine. You need to be looking around where the plumber did the work to see if by chance the thermostat cable has been cut by accident.

Ken, AC Cooling Wizard

[Markjosephp]

Hi there,

Thanks for the assistance, @CoolingWizard and @EdwardT.

@nicolecandy44, I'm checking in to make sure that you've seen our response. Please let us know if you have any other questions or concern.

Best regards,

Mark

[Markjosephp]

Hello nicolecandy44,

It has been a few days since the last reply, and I am going to lock the thread in 24 hours. If you have any questions, please feel free to create a new post.

Best regards,

Mark

[EdwardT]

Hi folks,

@CoolingWizard and Todbone, thanks for the help!

@nicolecandy44, thanks for posting. To isolate the issue further, you could try the steps on this link for some troubleshooting steps you could try.

Thanks,

Edward