Questions tagged [furnace]

The furnace is part of an HVAC or central heating system used to generate heat. Typically this is done with gas, a heat pump, or an electric element. For hot water and radiator based heating, use the boiler tag.

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53 views

Furnace Connect G Wire

I have a dual energy electric/oil furnace that is wired to a thermostat with 2 wires R and W. I don't have any AC. Inside the furnace there is a switch relay to control the fan but it is not connected ...
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0answers
39 views

Why isn't my furnace igniting?

I noticed cold air from my Carrier 58SS furnace. The main burners were not lighting. The pilot flame was strong, but yellow. When I tapped on the gas valve, the pilot shut off. I removed the pilot ...
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1answer
75 views

York furnace not firing up correctly

I have a York TG9S080B12MP11A up-flow configured natural gas furnace. We have had the furnace since 2007. I am having an issue where the furnace is not starting correctly. When I power up the blower ...
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1answer
74 views

Unable to locate filter on Gas Furnace

Can not find where the filter for this furnace is. It is a gas Rheem Criterion II. Have watched YouTube videos but none look like mine. Thermostat keeps saying filter needs replacement.
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0answers
26 views

Garage Furnace Runs Only 45 seconds at a time

I have an older Janitrol Moffat furnace in my garage. It was converted sometime in the past from propane to natural gas. It takes quite awhile for it to heat up enough for the fan to kick in and once ...
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2answers
588 views

Old furnace with no “C” terminal for wifi thermostat

I'm new to this forum and was wondering if I could get some help regarding installing a Honeywell WiFi thermostat that requires a "C" terminal. I currently have an older thermostat that has only 4 ...
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0answers
56 views

Replacing a motherboard on a Carrier 8000VS Furnace

Hi guys, I am trying to finalize the wiring of my new carrier motherboard. I have about four more wires to connect and the new motherboard is slightly different than the old one. The pictures I’ve ...
2
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1answer
7k views

Pilot won't stay lit after replacing thermocouple

The pilot won't stay lit on my furnace, when I release the button it just goes out. This started occurring after I did some gas plumbing and had to relight the pilot. I suspected the thermocouple ...
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0answers
455 views

Installing Ecobee3 with Trane Furance

I am installing an Ecobee3 and have found that, while the common wire exists, it is not connect to the furnace. The wiring schematic for my specific furnace can be found in this PDF There is no ...
2
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1answer
445 views

No power in r line after changed thermostat

I have a carrier furnace 2008, just changed my old thermostat to new nest thermostat, forgot to turn off the power. Now I have no power on my r line, checked short fuse still good, red light in front ...
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0answers
600 views

Constant cold air from vents with new downdraft furnace

Replaced with newer, high efficiency furnace and cold air constantly coming out of vents (except when furnace running). It's like the downdraft is totally free flowing and when windy outside very ...
2
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1answer
530 views

New Thermostat installed but compressor comes on immediately

I have a new Insteon Thermostat that I'm using to replace my prior Honeywell t-stat. This is installed to a relatively new HVAC system (both AC and Heat) that DOES have a "c" wire. I've attached the ...
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0answers
2k views

How can I reduce noise from an air handler unit in an open closet?

How can I reduce the noise from an air handler unit? I have a Goodman AR42-1 air handler unit in an open closet. The setup looks like this: When the air handler activates it sounds like this: ...
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2answers
1k views

Goodman gas burner not lighting

Goodman warm air gas furnace. Gas burner would not light.Status code light blinked continuously. Igniter glows red hot. I cleaned flame sensor with fine grade sand paper. Checked transformer line ...
2
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1answer
146 views

Why would my Maytag FG6RC high efficiency furnace restart in the middle of a heating cycle?

My furnace is probably 7-8 years old, and this heating season the furnace has developed a strange problem. The furnace starts normally, but before the temperature reaches the thermostat setting the ...
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0answers
1k views

Are w1 and w2 both energized during a second stage heat call from the thermostat?

Short version: does two-stage thermostat always close W1 circuit when it closes W2 circuit, or they might be closed independently? Long version: I have two-stage furnace, currently connected to older ...
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0answers
331 views

Why won't my condenser turn on when I run my heat pump?

I have a York Affinity condenser. When I run my heat pump, I expect it to turn on somewhere in the cycle but it doesn't. It generally does this once a year. The usual fix is to cycle the power of the ...
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33 views

Only getting 15-16 volts from Furnace R and C

I recently purchased a smart thermostat. Because it needed a common wire and I only had a 3 wire setup, I ran a new thermostat wire to my furnace. However, I now get only 15 volts (inconsistently, ...
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34 views

Furnace blower cutting in and out during A/C use

Backstory: I fired up my air condition for the first time this season (single family house) and felt lukewarm air coming out of my ducts. When i went outside i saw that the condenser was not turning ...
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1answer
54 views

Line to AC dripping at the furnace

My line from my exterior AC unit is dripping at the furnace. The dripping over time has caused rusting and we've had to replace the control board under it. It appears the root cause of the problem ...
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1answer
41 views

Furnace with no “C” connection

I have a mobile home furnace. This furnace only has a 4 wire connection terminal, G,W,R,Y. I also have a condensing unit outside with the 24 volt 2 wires coming to the furnace. I know I connect one to ...
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1answer
23 views

Furnace Pressure Switch Testing

I have a ComfortMaker combination furnace/AC for the back part of my house. The furnace kicks in, but never heats up. No errors are reported. Started troubleshooting and took a peek at the pressure ...
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2answers
44 views

Pilot light keeps going out

I have a Coleman mobile home furnace and my pilot light keeps going out. I have replaced the thermocouple twice, cleaned the orfice, replace the gas regulator with a brand new one, and even crawled ...
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1answer
42 views

Adding split AC to a Dayton oil fired forced hot air furnace

I'm trying to add split central air to my Dayton oil fired forced hot air furnace, mod # 3E268A. The manual clearly says it can accept this but the terminal block in the unit only has (4) lugs. TT and ...
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1answer
59 views

How to troubleshoot gas supply not making it to some appliances

I recently purchased a home and once utilities were turned on I've been having issues with certain gas appliances. Some appliances required a normal amount of time to get the gas flowing after being ...
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1answer
30 views

How can I control my furnace fan from a secondary thermostat?

I have a WaterFurnace geothermal system with upper and lower level zones. I recently added an outdoor wood burner and my issue is that I want to use a secondary stat to run the furnace fan during the ...
1
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1answer
47 views

Furnace Short Cycling

My furnace is short-cycling. I've tried the following: replaced the flame sensor Shorted the thermostat heat demand signal Checked the blower capacitor Checked the air intake filter Checked the ...
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0answers
61 views

Can I provide low-voltage power for an HVAC humidifier from a standard outlet?

I recently bought an Aprilaire humidifier to replace an old one that came with the house, which I thought was broken. After connecting the water (which does work and isn't clogged) and the wiring to ...
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44 views

Furnace Repair Gone Wrong?

My furnace stopped working last Saturday so I started troubleshooting to find the problem. I found that the board was not providing 110V to my inducer motor. So I determined that I needed a new board. ...
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221 views

How to stop the humming noise coming from my gas furnace when on Auto Heat?

My gas furnace makes a humming noise when on Auto Heat, like as if the blower motor or capacitor was bad. However, the blower turns on and sounds fine when thermostat is set to fan ON rather than ...
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24 views

Furnace won't light when fan commanded on

House and furnace are 5 years old. Furnace is an Allied A95UH2V090C16S-07 and is interlocked to a Lifebreath HRV. Functioned fine up until a couple days ago. My wife calls me and tells me that ...
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0answers
66 views

Do I need to replace my pressure switch in my Goodman furnace?

We have a Goodman GKS9 Gas-Fired Warm Air Furnace. I've changed the air filter, cleaned the flame sensor, and checked the condensation pipes for clogs. They're clear. The behavior seems strange to me. ...
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1answer
42 views

burners out of sequence with blower motor

I have a Bryant furnace plus 90 model #398AAW036060D. I just changed the blower motor. In the last five years I've changed the main board, inducer board, pressure switch, and cleaned the igniter the ...
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49 views

Honeywell Thermostat to Nest E Dehumidification

I am trying to replace my Honeywell Prestige IAQ thermostats. I noticed that my downstairs thermostat has a dehumidification option (upstairs shows no such option). I checked the wiring at the ...
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116 views

Furnace not igniting with error E228

My furnace is Armstrong Air, A97USMV, today when turn on, the induce fan keep running but not ignition, then stopped with error code E228 (Unable to perform successful pressure switch calibration). ...
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23 views

How to Run Fan Only with Thermostar Furnace With G Wire

I have a Thermostar Furnace that works great for Heating our home. We do not have AC and do not want that. But, we do want to be able to just run the fan without heat. The W and RH wires were ...
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0answers
330 views

Where should I connect my C wire on Goodman GMP075-3 Rev.B

I am trying to install an ecobee4 to replace a digital battery powered thermostat. I removed the existing thermostat and found that there was a spare blue wire that was wrapped around the others that ...
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16 views

Do I need to replace the thermostat wiring leading to my boiler?

I have a boiler in an old building with four different apartments. There are two thermostats that call for heat from the boiler, and valves that direct the hot water to the respective part of the ...
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0answers
241 views

Lennox furnace 3 flashing lights

Have a new construction house, and lived here about 2.5 yrs. Turned on my furnace last night worked fine. This morning, it kept turning on then kicking off with no burners coming on. I noticed the ...
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108 views

Furnace draft inducer switch tripping

I have an older furnace and a brand new natural gas instant water heater that I installed. I only start this way because the furnace had one thing break last year, so I'm not sure if things on it are ...
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1answer
48 views

Fan comes on but the air conditioner does not

During hot days when the air conditioner is on a lot it comes to a point in the evening when the air conditioner shuts down and the fan (from furnace) stays on. This will go on all night as the house ...
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0answers
45 views

Converted Oil Furnace to Natural Gas - Fuel Smell Issue

This weekend, we had our fuel oil furnace replaced with a natural gas one. The oil furnace broke near the end of the winter and we were waiting for a deal to kick in on a whole new furnace + A/C unit. ...
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0answers
92 views

Correct wiring for Nest thermostat with dual HVAC system

Trying to wire up this new-fangled Nest Thermostat E (the cheapy edition) to my home HVAC system, but unsure of what to do. At the thermostat, I have G, W, Y, R, AND Rc wires, but the R and Rc wires ...
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1k views

Furnace Mainboard wiring with AC unit

I went to install a Nest on my upstairs HVAC unit. After installing the Nest I thought it was functioning properly. The next afternoon I came back to the house It was still hot, so looking into this ...
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0answers
46 views

Lennox G20 furnace

I was reading about using the T terminal for the C wire for internet thermostat. I have different wiring Thermostat Furnace RC R W. W Y Blank Rh T G. G ...
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2answers
95 views

how to insulate attic that contains high-efficiency furnace?

We have an older home with a separate high efficiency furnace for the second floor. It sits on a floored area of the attic. We have virtually no insulation and I've gotten various recommendations ...
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0answers
549 views

Goodman furnace starts after turning on / off 7 times

I have a Goodman furnace from 2000 has been running great until recently it does not seem to cinc with thermostat. when you shut unit down and turn back on it will go through all motions of starting ...
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0answers
43 views

furnace wont kick in

My furnace seems to work intermittently. overnight its seems to stop... i have checked the thermostat and it shows says it is heating. fan is on auto, but nothing coming out. when i turn heat to off, ...
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23 views

coleman gas heat only furnace,

When heat comes on, furnace runs for about 8 mins then cycles off. When the heat clicks off I get a switch open code from the board. While the furnace is running I get a normal operation code. As soon ...
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2answers
334 views

Furnace Blower fan doesn't start

I have a keeprite high efficiency furnace that Was a part of my new house. It's 2016. The Honeywell thermostat is set at 23 deg C. This is what happens when the temperature is below the cut-off I ...