Ask Experts Questions for FREE Help!
  Advanced
Register  |  Log in  
   Ask    
 Answer  
  Help  

Ask QuestionsprogressAnswer QuestionsprogressBuild ReputationprogressBecome an Expert
 
Free Answers in 3 Easy Steps

Register Now
3 Steps

At Ask Me Help Desk you can ask questions in any topic and have them answered for free by our experts. To ask questions or participate in answering them you must register for a free account. By registering you will be able to:
  • Get free answers from experts in any of our 300+ topics.
  • Accept money for answers that you provide.
  • Communicate privately with other members (PM).
  • See fewer ads.

Home > Home & Garden > Heating & Air Conditioning   »   How to wire 3 wire 2 zone cooling only to Honeywell thermostat

 
Thread Tools Display Modes
Question
 
 
#1  
Old Apr 21, 2008, 10:09 AM
nfasone
New Member
nfasone is offline
 
Join Date: Apr 2008
Posts: 17
nfasone See this member's comment history on his/her Profile page.
How to wire 3 wire 2 zone cooling only to Honeywell thermostat

I currently have two zones for cooling only and the thermostat wires are red, blue and white. The red is labeled Rc which is easy, the white is labeled W Heat (this doesnt make sense to me) and the blue is labeled cool? What i think i need to do is connect the red to the Rc on the thermostat, the blue wire (cool) to the Y, cooling connection and the white is where i am confused, it will either go to W or to G for Fan??? Why its labeled to W Heat is throwing me off.

Reply With Quote
 
     

Answers
 
 
Old Apr 21, 2008, 10:11 AM   #2  
Heating & Air Conditioning Expert
hvac1000 is offline
 
hvac1000's Avatar
 
Join Date: Aug 2005
Location: Ohio
Posts: 5,433
hvac1000 See this member's comment history on his/her Profile page.hvac1000 See this member's comment history on his/her Profile page.
Thermostat model numbers?
Why are you changing thermostats?
Did the original system work OK?
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 10:14 AM   #3  
New Member
nfasone is offline
 
Join Date: Apr 2008
Posts: 17
nfasone See this member's comment history on his/her Profile page.
The old ones are Robertshaw, not sure of the model number the new one is the honeywell Rth6500B. The old ones are shot and i wanted to put programmable ones in for efficiency
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 11:04 AM   #4  
Heating & Air Conditioning Expert
hvac1000 is offline
 
hvac1000's Avatar
 
Join Date: Aug 2005
Location: Ohio
Posts: 5,433
hvac1000 See this member's comment history on his/her Profile page.hvac1000 See this member's comment history on his/her Profile page.
The old ones are shot

IT does not make a difference if it is shot or not.
Did you follow the directions with the new thermostat about labeling the old thermostat wires designations and colors?

If not you may have to trace back all wires to see where they go on the operating controls.

OLD thermostat model number???
I will see if I can locate a wiring diagram for the old thermostat without it I can be of no help.
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 11:09 AM   #5  
New Member
nfasone is offline
 
Join Date: Apr 2008
Posts: 17
nfasone See this member's comment history on his/her Profile page.
Yes, the wire label designations for the white is W Heat, for the Red it is Rc and for the Blue all it said was Cool. I am currently in the office now and not in front of it however thats all they said. The model of thermostat is the 200 series from what i can tell by looking online. IThe builder 9 years ago wasnt very specific on many things. Those labels were in black in on the thermostat.
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 11:11 AM   #6  
New Member
nfasone is offline
 
Join Date: Apr 2008
Posts: 17
nfasone See this member's comment history on his/her Profile page.
I really appreciate your help by the way.. I am sure i can figure it out just dont want to risk shorting something out, but think i will be ok as long as the Red Rc is connected to the Rc on the thermostat. Then i can try the others? Any thoughts on that?
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 11:15 AM   #7  
New Member
nfasone is offline
 
Join Date: Apr 2008
Posts: 17
nfasone See this member's comment history on his/her Profile page.
The B and W are to open and close the damper valves, i just dont know how that translates to the new thermostat.
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 11:16 AM   #8  
Heating & Air Conditioning Expert
hvac1000 is offline
 
hvac1000's Avatar
 
Join Date: Aug 2005
Location: Ohio
Posts: 5,433
hvac1000 See this member's comment history on his/her Profile page.hvac1000 See this member's comment history on his/her Profile page.
I woulkd wire the new thermostat just the way the old one was wired. If uncomfortable with the situation I would seek professional help.
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 11:20 AM   #9  
Heating & Air Conditioning Expert
hvac1000 is offline
 
hvac1000's Avatar
 
Join Date: Aug 2005
Location: Ohio
Posts: 5,433
hvac1000 See this member's comment history on his/her Profile page.hvac1000 See this member's comment history on his/her Profile page.
The B and W are to open and close the damper valves, i just dont know how that translates to the new thermostat.

I have no idea how it was wired to start with butif Band W are active on the old stat you might have the wrong new stat to start with.
  Reply With Quote
 
     
 
 
Old Apr 21, 2008, 11:54 AM   #10  
New Member
nfasone is offline
 
Join Date: Apr 2008
Posts: 17
nfasone See this member's comment history on his/her Profile page.
Thanks i actually did some more research and i have the Robertshaw TX400 and the coding is as follows:

w = heat
r = common
b = cool


Can I ask you one more quick thing? The R = Common does that mean i should not conenct it to Rc? I think this goes to Rc, and then i will connect w to heat and b to y on the new one which is cool. By the way this site is great and i appreciate your help.
  Reply With Quote
 
     


Thread Tools
Display Modes

 
Similar Sponsors

Similar Threads
Question Asker Forum Answers Last Post
Replacing 3-wire thermostat with Honeywell RTH230B khnervick Heating & Air Conditioning 1 Jan 4, 2008 09:40 PM
Honeywell thermostat pro 8000, Why remove jumper wire? Bad Boy Andy Heating & Air Conditioning 2 Dec 2, 2007 08:39 PM
Janitrol 7 wire to Honeywell RTH230B 5 wire Professional Rookie Heating & Air Conditioning 3 Aug 26, 2007 12:23 PM
Honeywell thermostat - old orange wire tmm Heating & Air Conditioning 5 Aug 10, 2007 08:57 AM
how to wire a new honeywell thermostat vm8444 Heating & Air Conditioning 4 Jun 8, 2007 07:49 AM




Copyright ©2003 - 2007, Ask Me Help Desk.
All times are GMT -8. The time now is 04:36 AM.