Explore answers about Mercury Switch

Boiler Model 234-5PN Series 'C' Lights; then goes out in

Bryant Boiler Model 234-5PN Series 'C' Lights; then goes out in about 2 - 5 seconds. Then will relight again. Pilot stays lit. Heavy soot. Same problem with chimney pipe removed.JA: How long has this been going on? And how severe is the problem?Customer: Report of no heat yesterday.JA: Do you plan on doing the work yourself?Customer: Sure. If practical & safe. Looks like it needs a good cleaning and a switch or 2JA: Anything else we should know to help you best?Customer: I think that is it. I have no wiring diagrams or I'd be further along.

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Rick

Supervisor

26,298 satisfied customers
I have a Comfortaire GMUH75-E3N furnace with electronic

I have a Comfortaire GMUH75-E3N furnace with electronic ignition. The problem is that it suddenly stopped igniting and the fan kicks on and won't shut off. I have relaced the filter and a fan limit switch but that didn't change anything. The igniter will not come on and the furnace just blows cold air. I also replaced the old mercury switch thermostat with no effect. Help!JA: Did you double-check the thermostat's settings? And what about the filters?Customer: The thermostat is new and the wiring diagram was followed. The filter is new.JA: Do you plan on doing the work yourself?Customer: I'm hoping to.....JA: Anything else we should know to help you best?Customer: I ordered a new ciruit board but am a little hesitant about undertaking that task. On the circuit board are two dip switches and they are currently set to "off." Is that the correct setting?

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Gaztech

Owner

Vocational, Technical or Trade School

872 satisfied customers
Living Room zone is set to 68 degrees, but room is at 75

Living Room zone is set to 68 degrees, but room is at 75 degrees and is not going down even when we lower it.JA: I'll do all I can to help. How long have you been dealing with this?Customer: this is the third dayJA: Do you plan on doing the work yourself?Customer: it is a standard round honeywell manual thermostat - Class 2 30 watt. We hope to be able to fix it ourselvesJA: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat?Customer: The rest of zones are fine in the house.JA: Anything else we should know to help you best?Customer: It has the mercury switch in it.

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Rick

Supervisor

26,298 satisfied customers
Is there a replacement for a mercury flame safety switch for

Is there a replacement for a mercury flame safety switch for my gas fireplaceJA: Just to clarify, what type of fireplace is this?Customer: Martin Industries DV200AJA: Do you plan on doing the work yourself?Customer: Not necessarilyJA: Anything else we should know to help you best?Customer: It has a pilot light with a thermopile. The sensor end of the mercury switch broke off.

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HVAC Guru

Service Technician

Associate Degree

27,924 satisfied customers
I replaced my thermostat a few weeks ago and also the

I replaced my thermostat a few weeks ago and also the circuit board in the air handler to repair the AC now it will not switch to heat, it comes on but with thermostat in heat mode it is still running ACJA: Did you double-check the thermostat's settings? And what about the filters?Customer: yesJA: Do you plan on doing the work yourself?Customer: i want to tryJA: Anything else we should know to help you best?Customer: I was on here looking for wiring diagram to make sure I have everything wired right

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BillyHvac

Journeyman Service Technician

State Licensed Mechanical Contractor

12,368 satisfied customers
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

Supervisor

26,298 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

27,924 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

Supervisor

26,298 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

11,086 satisfied customers
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Questions you might consider asking
  • Installed a non-programmable thermostat RTH 111B. After installation unit a/c unit can on an ran for about 5 minutes. Unit then cut off and compressor would not come on. I re-installed the old mercury switch thermostat and the a/c worked fine. Any idea what the issue could be?
  • I have an old HW thermostat # 786A7X103A1 (mercury switch). What is best programmable Thermostat or what wiring do I have to be aware of?
  • I have a instaflame fire place the piolet lights but will not stay on, is the part I need a Thermopile sensor or a mercury switch the Model # DV 36 RN. hoping you can help.
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