(Heating, Ventilating, and Air Conditioning) For questions about installing, repairing, and troubleshooting HVAC systems.

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2
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0answers
34 views

Should I get a single- or two-stage furnace for my three-floor brick home?

I just bought a house that has a furnace on its last legs. The house is 1941 masonry in Chicago with 3 floors: finished basement, first floor and a second floor that is a converted attic with vaulted ...
0
votes
1answer
147 views

How can I adjust a whole-house ventilation bathroom exhaust timer?

We have a home built in 2008 in west-central Minnesota. As a cost-saving (I perceive it as such, and may be mistaken) measure to fulfill air quality and venting code, the builder set up an upstairs ...
0
votes
1answer
30 views

electric heater keeps needing to be reset by turning fan on and off atleast every 1-2 days

My electric furnace is about 23 years old, it quits working but does not trip a breaker. It feels warm to hot at furnace and just kind of clicks occasionaly when I turn thermostat up to 90 to try and ...
2
votes
1answer
143 views

Can't get my AC to turn on at all

Recently our AC stopped working. The thermostat is working properly, but the unit just started blowing hot air. I've never worked on a AC before, but I was trying to save some money. Anyway started ...
0
votes
1answer
77 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 ...
0
votes
1answer
1k views

What could be causing my Lennox furnace to blow cool air?

My Lennox outside furnace is blowing cool air, not hot even when the burner is lit. It takes 3 times longer to heat the house than it should. I just had the draft motor replace about a month ago and ...
0
votes
1answer
35 views

Oil furnace fan won't shut off when “heat” plug is connected to control board

I was changing my thermostat and I attempted to make the swap live without turning power off. When I connected new thermostat, the fan kept running. Ruled out bad thermostat and wire short by ...
0
votes
2answers
79 views

Furnace fan works properly intermittently

My furnace fan sometimes stays on and runs continuously. I can stop it by flipping the breaker for the furnace on and off. It then stays off. When heat is called for, the fan comes on again and ...
2
votes
3answers
3k views

What is going on with my central air?

I have a re-occurring issue with my central air. I have changed filters, cleaned all three intake vents and even had a serviceman out on three different occasions (two separate companies). My problem ...
2
votes
2answers
18 views

Zoned heating system very warm even without heat on upstairs?

I know heat rises, but our 1st story floorplan house gets pretty darn warm during the winter months. Other than turning on the AC or opening windows in the upper story zone, anything else that could ...
0
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2answers
302 views

Gap between 6“ dia wall thimble & 6” hvac pipe

I bought a 6" dia aluminum wall thimble to vent my 6" dia hvac steel exhaust pipe through to the outside. However, the diameter of the 6" thimble is actually 6 3/4". How do I effectively insulate the ...
0
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2answers
145 views

Issues after capacitor replaced on AC unit

Had a checkup on my AC/ furnace a couple weeks ago. The technician said the capacitor leaking oil and not pulling enough amps. He recommended me getting a whole new system. (My house was built 6 yrs ...
2
votes
1answer
36 views

What inspections/maintenance should be done before first air conditioning of summer?

I'm a typically handy guy who knows his limits. I recently moved into a new house so am unfamiliar with the history of the equipment. Before I switch the thermostat to A/C for the first time this ...
0
votes
1answer
13 views

I have an electric furnace that sometimes blows cold air

I have an electric furnace that blow cold air sometimes. I replaced the thermostat and that did not fix it. The fan blows fine. If I shut if off for a few minutes and then try again, about half the ...
0
votes
1answer
535 views

What type of dryer best handles long exhaust vents?

I have a very long exhaust line (about 5 meters) from the dryer and have issues with moisture staying in it when I do laundry. Since the old dryer broke down, I am now shopping around for a new dryer ...
1
vote
1answer
3k views

Troubleshoot AC issue, no inside blower

I need help troubleshooting Rheem RAHE-036JAS, Armstrong G1N80AU125D20C-1, Honeywell ST9160B 1068 Board, Honeywell SV9520H 8034 Gas Valve. About a week ago, AC and Heat were working fine. After ...
1
vote
2answers
251 views

Trane xv80 3 blinks

Trying to be as thorough and concise as I can, zero experience with hvac. I have a year 2002 Trane xv80 that is giving me the three blink code, which indicates a pressure switch issue. I ...
0
votes
2answers
38 views

How should I prepare for duct cleaning?

Before calling the professional to clean the ducts and remove the dust(I think both of them go together) what should I do?
2
votes
2answers
853 views

Wifi Thermostat to Reznor Garage Heater. No “C” wire connection on terminal strip

I just had a 75000 btu Reznor UDAP garage heater installed. Can I run a "C" wire for a smart thermostat if I don't have a C connection on the terminal strip? There is a C connection on the circuit ...
1
vote
1answer
20 views

Why might a thermostat refuse to switch from Heat mode to Cool mode?

I have this Honeywell RTHL2410C programmable thermostat and typical Florida electric AC system. Starting this Spring, it has started behaving strangely when switching from Heat to Cool mode. The ...
1
vote
1answer
35 views

Limit switch doesn't function on oil furnace

my limit switch on my oil furnace does not shut off the burner when it hits the limit.I replaced the limit twice maybe I had a bad one still no luck . While furnace was running I took the thermostat ...
1
vote
3answers
43 views

Duct sizing impact on flow

We have a ranch with a wood fireplace in the living room. It's fantastic at heating the main living area, but the bedrooms down the hall get left in the cold. I'm going to install insulated flexible ...
1
vote
1answer
455 views

Why does the blower in the attic vibrate during heating when it is really cold?

We have a Carrier heat pump system in our home, and the blower is located in the attic. When it is especially cold, the blower runs on high (there are three levels: high, medium, low). During this ...
0
votes
0answers
8 views

Have Goodman GHM81405 gas furnace that begins to ignite and then stops

I have a Goodman GHM81405 gas furnace that begins to ignite, and then turns off after a couple of seconds. I have cleaned the ignitor but it still does the same thing.
1
vote
3answers
58 views

What's the most cost effective way of ventilation automation given no prior knowledge in the field

I have 3 fans for air inflow, and 3 fans for extract, all in one big hall. Currently I set the power of their motors with dimmers myself, looking at CO2 and temperature readings. I want to replace ...
1
vote
1answer
207 views

Why would only 1/3 of my registers be blowing warm air?

I have a Coleman gas furnace in a wall space in my house which somehow shares the blower on my a/c unit on the roof because it turns on when furnace is called to start, though it does bump up after a ...
0
votes
1answer
29 views

Could a leaking boiler be fixed?

I'm having a leaking hole in the cast iron boiler tube so does it mean that its time for a new boiler or is there any way it could be permanently fixed?
0
votes
1answer
32 views

Does thermostat need to be grounded?

If a thermostat is connected to an air handler, which is connected to the main panel and has a ground wire, should one of the thermostat wires be connected to the ground?
1
vote
3answers
249 views

No AC. I have a few HVAC troubleshooting questions

I'm having issues with my AC. Basically, the symptom is that I feel cold air coming out of the vent, but it has no pressure, almost like I have to put my hand IN THE VENT COVER to feel any cold air. ...
1
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0answers
22 views

Thermostat replacement in a double wide

We have a new double wide and I want to replace the thermostat with a new programmable one. We took off the old one and it has 3 red wires, 2 yellow, 1 white and 1 green. I get the 2 red indicate a ...
2
votes
1answer
4k views

can i use an inline exhaust to vent a kitchen and bathroom?

I have 2 bathrooms and a kitchen that are currently unvented. I would like to install an inline exhaust fan to service all three. I will be putting the exhaust fan just inside a gable that will have ...
3
votes
5answers
34k views

How much less power does a three-phase air conditioning unit use than a one phase unit?

I'm planning to install a 5 ton central AC. I'm deciding between a condensing unit that runs on 220V and a costlier unit that runs on 207Y three-phase. My understanding is that three-phase motors use ...
1
vote
3answers
108 views

Leakage in my pipes, how to densify/seal?

I've never built with pipes before so maybe I'd need some general advice regarding leakage. On a specific note, I've built a system (see picture) where it leaks practically everywhere. I've sealed it ...
9
votes
6answers
1k views

What type of regular maintenance should I be doing on my central air conditioning unit?

I have not done any maintenance on my central air conditioning system since I bought my house five years ago. Everything seems to be running fine but is there some sort of maintenance I should be ...
1
vote
3answers
3k views

What could be causing this leaky evaporator problem?

My apologizes if I do not know the correct terminology for some of the parts. I will try my best though. We have a Trane A/C system that is causing us a headache. It is causing water damage in our ...
1
vote
1answer
34 views

Blower motor runs won't shut off no heat

My furnace is set at 72, my house is 64. I have no heat, and when I turn the thermostat off, it continually runs. When I'm running the air conditioner, it blows heat. What is a possible cause?
1
vote
2answers
46 views

A/C tune-up: “Condenser fan motor drawing high amperage”

A local A/C company was offering a deal on a home heating/cooling "check-up". I've never worked with this particular company before, and I've had some bad experiences in the past (different home, ...
2
votes
1answer
218 views

AC not cooling using heat pump

I just bought a house and this is my first experience with using a heat pump. I have put in several hours of research and understand how it works but I need someone that has experience to give me some ...
5
votes
2answers
11k views

Is it OK to have heating registers and returns near the ceiling?

I've got a question about a new house - a friend of my mother's is buying a new place and when she did a walkthrough (before the drywall was up), she noticed that all the heating registers and returns ...
0
votes
2answers
79 views

The house is not cooling

What would cause the outside ac motor to run than stop than start up again and continue this random stop and start cycle constantly. The house stopped cooling
1
vote
1answer
26 views

Thermal Expansion and Contraction in Two Story Townhome

I live in California in the city of Chatsworth to be exact. I live in a two story Townhome and for the most part when I sleep in my bedroom it's very quiet. Occasionally there will be nights sometimes ...
0
votes
0answers
10 views

GeneralAire 1137 & Honeywell Wi-Fi Color Touchscreen Thermostat

I have a GeneralAire 1137 power humidifier attached to my furnace. It was never wired to the humidistat it came with, basically the installer ran the wires to my bedroom next to my furnace ...
5
votes
2answers
70 views

Can I install A/C in a home built in 1924 which has round heat ducts in the ceiling?

Can I install A/C in a home built in 1924 which has round heat ducts in the ceiling? I am looking at homes to purchase in Milwaukee, WI. The home seems to have all it's ductwork above the ceiling, as ...
4
votes
4answers
2k views

Do I need to level the outdoor AC cooling unit?

I've read somewhere that the outdoor AC unit needs to be leveled. My outdoor unit is a bit slanted due to the floor not being completely flat (pic below). However, I don't see any obvious structural ...
5
votes
2answers
5k views

How do I install a jump duct?

Our master bedroom is considerably warmer than the living/dining/kitchen area of our house, and we've been setting the thermostat quite lower than we'd like in order for the bedroom to get cool enough ...
2
votes
2answers
71 views

How can I get better HVAC airflow?

I recently purchased my house which was a new construction. Several of the vents are getting poor airflow but the installation company simply said it was normal but I suspect otherwise. I recently ...
1
vote
2answers
399 views

Smart Thermostat - No C-Wire - No Controller Board

This one seems to be a little different from previous questions on the subject. Here is the dilemma, I don't see a transformer. I have included a few pics. There are Three wire bundles. For ease ...
0
votes
0answers
26 views

Why does my furnace blower fan intermittently hesitate for a second then continue?

Recently I had my 5 year old gas furnace serviced to replace a failed exhaust fan. Ever since, when the heat blower fan runs, it hesitates (stops) for about a second, about every 30 to 60 seconds, ...
1
vote
3answers
3k views

How can I heat up my apartment to kill bedbugs in Southeast Asia?

I have a bedbug problem in my apartment and I want to fix it myself with heat. (I do not want chemicals sprayed around.) Apparently, getting a room to 140 degrees for two hours is sufficient to kill ...
3
votes
3answers
128 views

Was this furnace installed properly?

I am looking to answer the following: Was this job done properly, and if not, then how really bad it is? And should I hire this contractor again ? Product: Ruud RGTM10ERBJS 100K BTU 95% ...