Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC


Thread Tools Search this Thread Display Modes
Old 06-09-2012, 09:59 AM   #1
Join Date: Nov 2006
Posts: 291
Rewards Points: 250

Mystery circuit - between air handler and thermostat. What could it be???

I'm trying to come up with some possible theories of what kind of circuits could exist between a thermostat wire and air handler??

- forced air electric, 2 zones
- Zone 1 is main house
- Zone 2 is wing of house controlled by a separate thermostat that actuates a damper to redirect air handler output to that wing of the house.

Zone 2 works fine, but when tracing the thermostat wiring for Zone 1 there appears to be some kind of circuit in the thermostat wiring somewhere well outside of the air handler. Whatever this circuit is, it's not easily accessible/identifiable. The thermostat wiring runs right alongside zone 1's hot air outlet duct.

(ie With Zone 1 thermostat wiring disconnected at AH and Thermo I measure 2 ohms red to red but 185 ohms white to white. That suggest possibly a relay coil???)

What possible circuits could be in line between a thermostat and air handler. Maybe a second damper?? What else is common??


hennyh is offline   Reply With Quote
Old 06-09-2012, 11:09 PM   #2
Msradell's Avatar
Join Date: Sep 2011
Location: Louisville Kentucky
Posts: 1,260
Rewards Points: 666

Mystery circuit - between air handler and thermostat. What could it be???

The only thing I could think of would be an additional damper. That's very normal in a two zone system so that either zone can call for heat/air while the other one is satisfied.

Msradell is offline   Reply With Quote
Old 06-10-2012, 07:36 AM   #3
An old Tradesmen
Join Date: Oct 2008
Location: PA
Posts: 25,965
Rewards Points: 3,600

Mystery circuit - between air handler and thermostat. What could it be???

Probably a zone panel.
beenthere is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Air handler blower will not come on? davvid20120 HVAC 8 04-01-2012 01:55 PM
weathertron Mecury Thermostat VickiL HVAC 4 02-06-2011 05:32 PM
Upgraded to new Hunter model 44860 thermostat and now no emergency heat hlmaint HVAC 0 01-08-2010 02:17 PM
Problem with Air Handler wiring connection to Outdoor Unit & Thermostat miamikk HVAC 0 09-29-2009 08:02 PM
So lost - electrical requirements please help lapsis9 HVAC 4 12-20-2006 09:09 PM

Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.