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Well i am trying to figure out why yet another thermo has

well i am trying to figure out why yet another thermo has bit the dust (3rd) replaced an old mercury with this honeywell, just for looks mainly , they seem to last about a year then wont call for heat

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Rick

Owner

23,588 satisfied customers
My very old thermostat (mercury switch) quit working last

my very old thermostat (mercury switch) quit working last night. we have a heat pump with backup / emergency electric heat. i purchased a Honeywell rth6350d at menards today as it read on the package it was compatible / would work with electric back up and heat pump the wires from tstat to furnace are as follows blue=electric heat, white= to heat pump, brown=common, orange=to heat pump, green=fan, red=power from 24v transformer inside of furnace, yellow= cooling/ heat pump, need help determining where orange,whiteblue and brown need to land to get the heat back on. thank you ,Brian

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HVAC Guru

Service Technician

Associate Degree

25,318 satisfied customers
I have a natural gas furnace that is not coming on when the

I have a natural gas furnace that is not coming on when the thermostat ( Honeywell digital, programmable,but not touch screen, must have been installed years ago) indicates that it is calling for heat. Tell me how I can bypass the thermostat so that the gas control valve can be tested directly. This is a 70% 1987 Trane furnace (model # ***** serial # *****) labeled "Executive high efficiency" (no longer can be called a high efficiency furnace!). There is no circuit board. It has a White-Rogers mercury switch automatic pilot control switch and an automatic ignition module, both of which are connected to the control valve. The valve is the OEM VAl (victory, ant, Larry)02622. It appears to be no longer available. The replacement has been id'd as White-Rogers 36C84-912.I have 4 wires connected to the thermostat: white, yellow, red and green. Which can I connect to send a heat signal to the furnace?

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Rick

Owner

23,588 satisfied customers
Will a Honeywell RTH7600, RET97 Series be used to replace a

will a Honeywell RTH7600, RET97 Series be used to replace a old two mercury switch t'statThe older t'stat controls heat and air condition using a "heat pump" there is a 6 wire cable connecting the "tstat" to the HVAC system- Yellow connects to Y terminal -Green to G -Red to R - Orange to O - White to W2 - Blue to CHow should these wires be connected to Your RTH7600

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Airheatman

Heating & Air Conditioning Contractor

6 years college

9,742 satisfied customers
I have a Honeywell class 2 lr1620 30 watt thermostat. No

Hello .. I have a Honeywell class 2 lr1620 30 watt thermostat. No response. No fan no emergency heat...Was working last week. Is this the thermostat? Or the system itself? Is there a reset for the stat?

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gotoman for ac

HVAC Service manager and owner

Associate Degree

5,270 satisfied customers
I have a similar question to some of the earlier THX9321

Hi, I have a similar question to some of the earlier THX9321 questions. We have a very old Honeywell thermostat, round, with a mercury switch! There are four wires coming from the wall: red, green, blue, and white. We have a gas furnace and an A/C unit. On the old thermostat: red went to R; green went to G; blue went to Y; and white went to W. So, where do these wires go in the THX9321? The manual is very confusing. Thank you very much.

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BillyHvac

Journeyman Service Technician

State Licensed Mechanical Contractor

11,630 satisfied customers
Rheem Criterion 2 furnace RGPH -10eamer Unit starts as

Rheem Criterion 2 furnace RGPH -10eamer Unit starts as normal but keeps heating way past set temp on thermostat also no LED lights on PCB when running

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Douglas

Vocational, Technical or Trade Scho

3,300 satisfied customers
I am installing a new Honeywell RTH7000D Mu old 1979

I am installing a new Honeywell RTH7000DMu old 1979 thermostat only has 2 wires.White and black.How should wire the new thermostat?

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HVAC Guru

Service Technician

Associate Degree

25,318 satisfied customers
I am looking wiring diagram dual control Carrier

I am looking for a wiring diagram for a dual control Carrier thermostat, one that controls both air conditioning and heat in one stat. Here are numbers/information I find stamped inside the base plate:-30V max-LR95329-1-T874D1074-HH07AT172Any information on how to re-install the stat on the wall after the drywaller and painter removed it would be greatly appreciated or could you recommend a digital retrofit replacement stat that could or would be easier to install and operate.Thanks!!!Bob

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Airheatman

Heating & Air Conditioning Contractor

6 years college

9,742 satisfied customers
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