Trane Air handler…

[bella123]

 

i have normal 5 wires coming out of wall.  why does air handler only have 3 wires (see 2 pictures of air handler above) and none on W heat terminals even though my heat worked fine when it was connected to honeywell thermostat…now changing to nest and heat is acting weird.  Any help greatly appreciated! also attaching current nest config below…

 

[Markjosephp]

Hello bella123,

Thanks for taking the time to let us know about your inquiries. I'd be happy to take a look into this.

Based on your thermostat's wiring, it appears you have a heat pump system. To isolate, could you share with us a photo of your previous thermostat's wiring? Also, what's the make and model of your HVAC system?

I'll look forward to your response.

Regards,

Mark

[bella123]

Hi Mark,

I forgot to take a pic of the thermostat wiring before putting the nest on.  

It is a Trane Model TWE

Any help is appreciated!

Thank you

[Markjosephp]

Hi there,

I understand that you no longer have the wiring reference. Let's try another way so we can verify it.

Do you have a heat pump system? If yes, please look for your system's control board to see how the wires from your thermostat were originally installed. Based on the first pictures you've sent, the wire connected to the B terminal should be for the 24 V common, which should be connected to the C terminal for the Nest Thermostats. Also, do you know the purpose of the blue wire?

Please keep me posted.

Thanks,

Mark

[bella123]

I do not have a pump, I have an air handler... i posted the wiring images in my initial post.

[bella123]

In the initial images the blue wire does not look like it is connected on the air handler.  should i connect it to one of those terminals?  which one would i connect it to?

[bella123]

Could still use some help.

Greatly appreciated!

[Markjosephp]

Hi bella123,

Thanks for clarifying that you don't have a heat pump system. In this case, move the white wire to the W1 terminal and connect the blue wire to the C terminal. After the wiring changes, restart the thermostat by pressing and holding the screen for 10 seconds until it shuts down to restart, and let me know how it goes.

Regards,

Mark

[Markjosephp]

Hey there,

I'm checking back in. Were you able to do the steps above? I'd be glad to hear from you — I'd like to make sure everything is working.

Thanks,

Mark

[Markjosephp]

Hello bella123,

I'm checking in to make sure that you've seen my response. Please let us know if you have any additional questions or concerns before we lock this thread in 24 hours.

Thanks,

Mark

[bella123]

Thank you so much for following up.  There is no blue wire connected on the air handler.  i see in the pic i sent you a blue wire is coiled around the green red white n yellow wires but there is no C on the terminal plate to connect it.  If i move the white wire to the W terminal should i connect that loose wire to the B terminal where the white wire currently is?

[Markjosephp]

Hi bella123,

Thanks for getting back to us and for letting me know. Going over these steps might help:
 

1. Move the white wire to the W1 terminal.
2. Connect the blue wire to the C terminal.
3. Refresh your thermostat. Go to Settings > Reset > Restart.
4. Activate the heat and wait for 5 minutes or so to observe.

Please note: turn off the power from your HVAC system at the breaker box before touching the wires, and keep me posted on how it goes.

Regards,

Mark

[bella123]

Hi Mark,

You say connect the blue wire to the C terminal but there is no C terminal like you mentioned on the air handler terminal pad.  Only G, T, Y1, Y2, R, O, B (which the white wire is currently connected to), W3, W2 and W1 (no white wires are on any of the W terminals). See pics from orig message.  So what terminal should i connect the blue wire to on the air handler terminal pad?

Thank you!

[Markjosephp]

Hello there,

I'm sorry for the late reply and for the confusion. It's moving the wires into your actual thermostat's base. How's it going? Have you tried re-configuring your thermostat's wiring? Please let me know if you need more help.

Regards,

Mark

[bella123]

 Hi Mark, Appreciate you checking in...so last week i had the handyman  reconfigure the Trane terminal only see attached pic of new config with blue wire connected and we connected the one blue wire only on the nest (same as nest pic in beginning of thread but with blue wore connected to the C terminal on nest) and turned it on however the ac did not turn on at all so before he left he confirmed the ac not coming on and we put the Trane terminal back to the original wiring) same as 1st picture in this thread and ac is working fine again but now the blue wire is not connected to trane term so it is a dead wire once again:( Any ideas? Should the nest have been reconfigured to match the new trane terminal?  If so which color wires would go what letter on nest terminals?

Thanks so much!

[Markjosephp]

Hey there,

Thanks for the update, and I appreciate your efforts in taking all the steps. Could you also please share a photo of your Trane thermostat's wiring? This is to see how it was originally labeled.

Thanks,

Mark

[Markjosephp]

Hello there,

I wanted to see if you still needed help. Please let us know if you have any other questions or concerns.

Thanks,

Mark

[EmersonB]

Hello everyone,

@bella123, just one quick final check in here since activity has slowed down. We'll be locking the thread in the next 24 hours, but if you still need help, we would be happy to keep it open. If there's more we can do, just let us know. 

I appreciate the help, Mark.

Best,
Emerson