Home Improvement Stack Exchange
Home Improvement Stack Exchange

Questions tagged [lennox]

29 questions
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votes
9 answers

Where should my furnace filter go in a Lennox G40UHX series furnace?

I have a Lennox G40UH(X) series furnace, which is installed in our attic (We have a single-story house on a slab). Because the furnace is installed in the attic, it is "laying down" on its side, and the incoming air is piped into what would be the…
Jared Harley
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1 answer

Connecting C-wire to Nest Thermostat for Lennox HVAC

My Nest thermostat has been running fine for quite a while, but recently it started complaining about low battery and wi-fi gets shut down due to power issues. I've been looking for the answer, and I found out that my Nest is not connected to the…
scifi88
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2
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1 answer

Why is my air conditioner running when the house is below the set temperature?

We recently had a whole new system installed for HVAC. We had a lennox furnace with dehumidifier and UV thing, along with the exterior lennox condenser for A/C. We have the iComfort S30 thermostat, and have the temperature set to: Temperature: Heat…
Barry Chapman
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2
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2 answers

Is it safe to replace a Furnace pressure switch with a different one?

So I had some problem with my gas furnace and a technician came by to install a new one but it doesn't have the same rating and only has one tube instead of two. He assures me it's fine but I thought all furnace repairs had to be made with OEM…
wjcmogui
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2
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3 answers

How do I connect the spare C wire to the old Lennox system (model # lennox g12q4-110)?

I am trying to install my Ecobee3 now. After finishing the connections, Ecobee did not power up. I did some reading and I believe the C-wire, though it is available is not connected to the power at the furnace-end (see the picture where you can find…
Visu
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1 answer

How to add C wire to a very old 2-wire Lennox G16 Gas Furnace?

I recently bought a Sensi Thermostat with Wifi to replace my vintage one. I thought it would work with my 2-wire heat only system because it has batteries , but found out that using the Wifi feature with batteries only with drain them in only a…
LennoxG16
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1 answer

how to change furnace filter (bottom return) for Lennox G43UF

I have a Lennox G43UF furnace and I am not sure if I need to have both a filter for a side return and bottom return. If I do (which sounds logical), where would the location of the bottom return filter be? I just bought a home and there were no…
dizzy
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4 answers

Why is my Lennox g40uh series furnace not turning on?

I have a Lennox g40uh series furnace and it just stopped working today. I can reset the furnace and can see that on the control board both LEDs (green and red) are blinking together which indicates the furnace is operating correctly. I can also hear…
Crackerjack
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How do I connect a C wire or C adapter to an older Lennox furnace with no terminal strip?

I have an older Lennox Conservator 3 G16 with no terminal strip. How do I connect a C wire or C adapter? From what I have seen online nothing matches my furnace.
Reylene
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1
vote
1 answer

Lennox Wiring for Ecobee SmartThermostat

Confused by the wiring, hope someone can help me out. At the furnace there's only four wires in the cable (R, B, G, and W), but at the other end, a yellow wire appears. It's not reflected in the picture of the thermostat wiring, but the blue wire is…
Sassbearilla
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Lennox G40UH erratic behaviour

I've spent the last couple of days troubleshooting my Lennox G40UH furnace. A couple of weeks ago, I noticed that the furnace would sometimes come on briefly (anywhere from one second to a couple of minutes), then shut down. But otherwise, it seemed…
Michael Cooper
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1
vote
1 answer

Vibrating PVC exhaust pipe from high efficiency furnace

We have a two year old house that has this heating season developed a vibration in the exhaust pipe that can be heard on the first floor of the house. It seems to have decreased as the season has progressed. The exhaust exits the furnace with a 2”…
John Kiczek
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2 answers

Lennox G23Q3/4-100-2 And Ecobee4

**Pictures attached to go along with my rambling explanation I have my Lennox G23Q3/4-100-2 natural gas furnace and my central air system that has been working since 1995 on a basic programmable thermostat and before my purchase of a new Ecobee4…
John Weidauer
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1 answer

How to set Nest Thermostat to control blower without heat

I have a Lennox G14Q3 propane furnace (forced air). I used the Nest/furnace setup last winter without any problems with just the W and R terminals. But, these summer days I would like to push air through the house with the blower (without heat) and…
Josh Jobin
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0
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0 answers

Furnace not working

I came home to my furnace having no power even to show trouble codes. I turned off my breaker opened the blower door and it had a blown 5 amp fuse on the curcuit board. I replaced the fuse turned the breaker back to on put the door back on and the…
Billy Korsen
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