Honewell thermostat wiring help needed


  #1  
Old 03-01-07, 01:28 AM
T
Member
Thread Starter
Join Date: Mar 2007
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Question Honewell thermostat wiring help needed

Hi, I am replacing my thermostat to a progammable unit. i have a hp with aux heat and i want to replace a honeywell(T874R) thermostat with a Honeywell (pro 8000 TH8320U).the old unit has 6 wires connected (R,Y,W,O ,B, AND G) there were also two wires tuckd away( black and brown) the new thermostat has two columns with the following with the RC and the R factory jumped--

conventional.........heat pump------both have the RC/R jumped
RC..(jumped with R)..RC--------i know R goes to R and G to G
R...(jumped with RC)..R---------y to y but where do W,O,and B go?
W........................O/B
Y...........................Y
G...........................G
C...........................C
i have read quite a few post and have an idea where they need to go but i rather know for sure than to take a guess and screw something up.
thanks for any help i can get
 
  #2  
Old 03-01-07, 02:01 AM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 2,148
Received 50 Likes on 44 Posts
Are you sure that the t-stat is supports aux. heat? It should have an aux or W2 terminal.

BTW heatpumps and programmable t-stats don't mix. On colder days, the heatpump alone won't be able to recover in a reasonable amount of time. The heat strips will run a lot more, offsetting any savings. Set it at one temperature and forget it.
 

Last edited by user 10; 03-01-07 at 02:19 AM.
  #3  
Old 03-01-07, 12:57 PM
Ed Imeduc's Avatar
Member
Join Date: Aug 2002
Location: Mountain Williams Missouri
Posts: 18,386
Likes: 0
Received 1 Like on 1 Post
Wink

Like said I dont like a programmable tstat on a heat pump. Slow pick up or it will turn the eme heat on to help. They do have some tstat now that pick up slow so it dont turn on the back up heat. But it takes a long time to get the temp back up in the home.
 
  #4  
Old 03-01-07, 05:57 PM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 2,148
Received 50 Likes on 44 Posts
Intelligent recovery or not, if the outdoor temperature is near the balance point (as it often is), a heatpump will never be able to recover without running the aux heat.

If you get a new t-stat which works with heat pumps, leave it on HOLD. Draft proof and add insulation to save energy.
 
  #5  
Old 03-01-07, 06:19 PM
A
Member
Join Date: Feb 2007
Location: Goodyear
Posts: 73
Likes: 0
Received 0 Likes on 0 Posts
Cool

first don't hook up the c-c or blue to c - bad mojo


r to either rh or rc-leave the jumper
stat
g- g
y- y - with a jumper to W
w- o
I'm pretty sure the honeywells have an aux terminal.
 
  #6  
Old 03-02-07, 06:56 PM
T
Member
Thread Starter
Join Date: Mar 2007
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Red face update on this question on tstat wiring question

my bad--- apperently i have two t stats with a different model # and different options on the wiring. the old tstat has the R,W,O,G,Y and B. the new tstats have the following (TH8320U) has the following optoins RC,R,O/B,Y,G,C,AUX,E,L and Y2 the other tstat (TH8110U) has the following options RC,R,O/B,Y,G,C ----both tstats have the RC and R factory jumped.
thanks for your help
 
  #7  
Old 03-02-07, 11:37 PM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 2,148
Received 50 Likes on 44 Posts
Return the TH8110U - it's incompatible with your system.

Follow the installation instructions - the newer models do not require a jumper from W to Y. (though you have to ensure that the system settings are correct for a heatpump so that Y is energized on a call for heat.

For the record:

R = Power
C = Common (directly back to the transformer)
G = Fan
Y = Outdoor unit contactor
Y2 = Second stage cooling (do not connect this unless you have a 2-stage unit)
W = Conventional heat (Furnace, electric heater, etc.)
W2/Aux = Auxiliary for heatpump or 2nd stage heat for a furnace
O = Reversing valve (energized in cooling or heating mode depending on the outdoor unit)
B = Reversing valve (either or re: O terminal)

**I'm not sure what having O and B means**

If you aren't familiar with the above, call a technician.
 
  #8  
Old 03-04-07, 07:37 PM
loco49's Avatar
Member
Join Date: Dec 2005
Location: kannapolis,nc
Posts: 22
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Muggle View Post
Are you sure that the t-stat is supports aux. heat? It should have an aux or W2 terminal.

BTW heatpumps and programmable t-stats don't mix. On colder days, the heatpump alone won't be able to recover in a reasonable amount of time. The heat strips will run a lot more, offsetting any savings. Set it at one temperature and forget it.
what make and model t-stat do you recomend for a heat pump.
last spring i replaced a older stat with a honeywell rth7000.a/c cycles good but in heat mode it runs all the time and electric bill has increased $60 plus a month as oppossed to last years.
 
  #9  
Old 03-14-07, 09:06 PM
N
Member
Join Date: Mar 2007
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Question also need help wiring a Honeywell TH8110U?

I need help wiring my thermostat similar to yours and so far have connected these wires:

Red = RC/R
White = W
Yellow = Y
Green = G

The heat works but can't get the A/C to work. I have a heat pump unit.

Did you get yours to work?

Thanks!



Originally Posted by TCDIY View Post
Hi, I am replacing my thermostat to a progammable unit. i have a hp with aux heat and i want to replace a honeywell(T874R) thermostat with a Honeywell (pro 8000 TH8320U).the old unit has 6 wires connected (R,Y,W,O ,B, AND G) there were also two wires tuckd away( black and brown) the new thermostat has two columns with the following with the RC and the R factory jumped--

conventional.........heat pump------both have the RC/R jumped
RC..(jumped with R)..RC--------i know R goes to R and G to G
R...(jumped with RC)..R---------y to y but where do W,O,and B go?
W........................O/B
Y...........................Y
G...........................G
C...........................C
i have read quite a few post and have an idea where they need to go but i rather know for sure than to take a guess and screw something up.
thanks for any help i can get
 
  #10  
Old 03-14-07, 11:05 PM
A
Member
Join Date: Feb 2007
Location: Goodyear
Posts: 73
Likes: 0
Received 0 Likes on 0 Posts
Cool

your going to need to energize your reversing valve circuit - either o or B
usually 0 but you need a heatpump t- stat
 
 

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