U1 wiring information - Honeywell to Nest


  #1  
Old 01-23-23, 10:04 AM
S
Member
Thread Starter
Join Date: Jan 2023
Posts: 3
Upvotes: 0
Received 0 Upvotes on 0 Posts
U1 wiring information - Honeywell to Nest

Hi,
I know people of already posted threads regarding the U1 wiring but I guess the wiring internally in the attic may differ on case by case basis.

So here I am presenting my case and looking for answers from the pros.

I've read the U1 could be connected to the humidifier/dehumidifier but it doesn't look like to me what i saw in the attic (I could be wrong).

Below are the pictures I've gathered.

Please let me know what needs to be done?

Thank you,

Siphons










 
  #2  
Old 01-24-23, 07:44 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 6,532
Received 95 Upvotes on 88 Posts
If black was wired that way it was incorrectly wired but it doesn't appear that your showing us the correct part of the zone control board.

The thermostat doesn't connect to the section of the zone control board labeled HVAC.

Do you have a humidifier?
 
  #3  
Old 01-24-23, 08:14 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,972
Received 4,149 Upvotes on 3,726 Posts
I don't recognize that board. We will need to see a picture of the entire board.
 
  #4  
Old 01-24-23, 10:03 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 6,532
Received 95 Upvotes on 88 Posts
Looks like an Aprilaire 6404 0r 6403 board.


 
PJmax voted this post useful.
  #5  
Old 01-25-23, 11:34 AM
S
Member
Thread Starter
Join Date: Jan 2023
Posts: 3
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for the responses.

Yes - it is indeed a 6403.

I'm sorry I'm new to this but how do I identify if I have a humidifier?

All i can see in the attic is a switch for a furnace and fresh air supply fan.

Thanks,

6403

Furnace Switch

Fresh Air Fan
 
  #6  
Old 01-25-23, 02:26 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,972
Received 4,149 Upvotes on 3,726 Posts
You have a fresh air vent system. Air King QuFresh is what is connected to U1.
Would need the model number off it to look up it's wiring connections.
Air King fresh air machine
 
  #7  
Old 01-26-23, 08:43 AM
S
Member
Thread Starter
Join Date: Jan 2023
Posts: 3
Upvotes: 0
Received 0 Upvotes on 0 Posts
Its a MQFAM and I'm not sure if its switched off but i can see some orange and black wires in there. But not sure how it is connected to the thermostat.


 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: