dual thermostats on Lennox CHA heat pump


  #1  
Old 11-20-07, 08:03 PM
T
Member
Thread Starter
Join Date: Nov 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
dual thermostats on Lennox CHA heat pump

I have a Lennox 5 ton central heat and air heat pump. All rooms are downstairs except one room upstairs with a duct to keep it cool. It stays hot up there. The thermostat is downstairs. Can I install a second thermostat upstairs and somehow connect it to the one downstairs? That way, when it gets hot upstairs it will kick on the unit.

Thanks, Tom
 
  #2  
Old 11-21-07, 08:18 AM
airman.1994's Avatar
Member
Join Date: Dec 2005
Location: VA
Posts: 5,491
Upvotes: 0
Received 8 Upvotes on 8 Posts
You have a duct issue. Fixing the duct should help this.
 
  #3  
Old 11-21-07, 05:26 PM
Jarredsdad's Avatar
Member
Join Date: Oct 2002
Location: Troy, VA
Posts: 1,392
Upvotes: 0
Received 0 Upvotes on 0 Posts
I'm with Airman, Duct problem.

To be fair to the question you asked the answer is yes you could. But, you really don't want to. Because, you would effectivly be moving the downstars tstat upstairs (which would actually be cheaper).

Either way if you ran the system to cool the upstairs the rest of the rooms would be freezing.

Have the duct work looked at. You might just need a return in the upstairs room.
 
  #4  
Old 11-22-07, 07:19 AM
T
Member
Thread Starter
Join Date: Nov 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
Dual termostats

Airman and Jarrodsdad - This is a new house in Tampa. We have had a little cool weather here and the stat downstairs is set at 78 and the air does not cut on cause it is in the low 70s. The upstairs room is exposed to the sun all day and it hits 90-92 degrees up there. The AC company wants to run another duct up there from the main unit in the garage. They are saying they will put a sensor(??) up there to signal the AC unit to cut on. Is this possible? The duct does not have a hole in it. Thanks - Tom.
 
  #5  
Old 11-22-07, 07:39 AM
Jarredsdad's Avatar
Member
Join Date: Oct 2002
Location: Troy, VA
Posts: 1,392
Upvotes: 0
Received 0 Upvotes on 0 Posts
Sounds like the company wants to put a "remote sensor" upstairs to control the whole system. Still, I think, this will only over cool the rest of the house.

If the a/c company can run another duct upstairs, why not look into a mini split for that area?
 
  #6  
Old 11-22-07, 02:32 PM
airman.1994's Avatar
Member
Join Date: Dec 2005
Location: VA
Posts: 5,491
Upvotes: 0
Received 8 Upvotes on 8 Posts
I agree! There should have been a 2nd unit for this area!
 
  #7  
Old 11-23-07, 12:31 PM
Ed Imeduc's Avatar
Member
Join Date: Aug 2002
Location: Mountain Williams Missouri
Posts: 17,505
Upvotes: 0
Received 1 Upvote on 1 Post
Wink

Have you tried to just close down a little all of the down stairs registers some ??? Do you have a return from that one room?? It Can help
 
  #8  
Old 12-15-07, 01:08 PM
T
Member
Thread Starter
Join Date: Nov 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
OK this is what the AC company is going to do, but I'd like your feedback on it before I let them proceed. They are going to convert it to a "zoned" system with a thermostat upstairs also. Bear in mind that the total house is 2400 SF. The room upstairs is about 400 SF. My concern is that when the upstairs stat kicks the AC on then the entire 5 ton unit will be running just to cool the upstairs. The AC company says that they will install some type of computer board in the AC to open and close the ducts going to the downstairs. When the upstairs tstat kicks it on, the downstairs will not get any of the air. They will also direct some of the air back into the return air intake when just the upstairs needs air.

Will this work, or is the AC company using a band aid approach just to make it work properly?
 
  #9  
Old 12-15-07, 01:24 PM
Ed Imeduc's Avatar
Member
Join Date: Aug 2002
Location: Mountain Williams Missouri
Posts: 17,505
Upvotes: 0
Received 1 Upvote on 1 Post
Wink

Id say forget it ........ Too turn on a 5 ton unit for just 400sq ft . You need a bypass in the duct and that will let cold air back to the coil then it can ice up. The unit will just turn and off on and off for that one room . That will cost you a lot of $$$$ ,BAD BAD. Like said get a mim split system for just that room. Also down there with FPL be sure you have a time delay on the unit. Cause of the bad power there.
 
  #10  
Old 12-15-07, 01:27 PM
airman.1994's Avatar
Member
Join Date: Dec 2005
Location: VA
Posts: 5,491
Upvotes: 0
Received 8 Upvotes on 8 Posts
Can it work! Yes id could. But like you said you will have a 5 ton unit running to cool a 1 ton load. I also don't think you can send that much air (1600 cfm?) back to the return with out over cooling. Id look into a mini split/ ductless.
 
  #11  
Old 12-15-07, 03:03 PM
T
Member
Thread Starter
Join Date: Nov 2007
Posts: 7
Upvotes: 0
Received 0 Upvotes on 0 Posts
The AC company does not want to install a mini because they said that will make the 5 ton unit too big for the downstairs area, plus it will probably make them look like they made a mistake. I'm pretty much a doityourselfer - how hard is it to install a mini system? Thanks - Tom
 
 

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