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My very old thermostat (mercury switch) quit working last night.
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
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?
I have (still) CGM-5-PI gas boiler - which stopped working
I have (still) CGM-5-PI gas boiler - which stopped working recent. There was buzzing/heating relay unit that i suspected, but i replaced it today, stopped humming, spark lights up, but main gas does not kick in. I removed pipe that had sparker/flame sensor attached to it, kiiinda cleaned sensor - and it actually lit up but when it stopped working (shut off when temp was enough) it didnt re-lite back. Should I replace flame sensor? or could be something else?
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
Heating & Air Conditioning Contractor
6 years college
I have a similar question to some of the earlier THX9321View more hvac questions
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.
Journeyman Service Technician
State Licensed Mechanical Contractor