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

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3
votes
2answers
544 views

What could cause a flame sensor to stop working so frequently?

Over a year ago after a month in our new house, we came back one evening to a cold home and after some googling, I found out that the flame sensor was dirty and the furnace was starting the flame and ...
0
votes
1answer
47 views

Fan coil wiring problem with new thermostat

I'm trying to upgrade to a new line voltage thermostat. The new thermostat has many more connections, including three fan speeds. My current system has a manual fan switch on the wall so all I need ...
1
vote
1answer
30 views

Why is it taking so long for my A/C to start?

When I turn my AC thermostat to cool, I can hear it click but the outside unit does not start and no air blows inside. Several hours later everything turns on and it works fine. If it turns off, ...
0
votes
2answers
117 views

What are the possible reasons I am not getting cold air from my air conditioner?

my heat pump outside is working but my central air conditioning/heating unit in the garage makes a hissing sound or faint sound of water running. There is air coming from the vents. The very last time ...
1
vote
2answers
4k views

What to do about different rooms in the house being a completely different temperature?

I moved into a 30 year old home last December. There is a problem with the HVAC. I have included a very crude drawing of the floor plan The problem is that I can't maintain a comfortable ...
1
vote
1answer
46 views

Is my HVAC system unbalanced?

I bought a home back in August and the previous owner had a new 3-ton HVAC system installed. Basically right now the HVAC is located in the upstairs hallway, and the way the duct is set up is there ...
1
vote
1answer
165 views

Adding a C/Common wire to HVAC system

So I'm looking for some help in identifying where I can attach a C/Common Wire to my HVAC system, but unfortunately my system doesn't have a control board that I can easily attach a powerkit to. For ...
2
votes
1answer
4k views

Does a compressor with a short to ground really require a complete system replacement?

My 24 year old home A\C went out some time Sunday morning. I had a tech come out and look at it, and was told that the compressor is shorted to ground, and that this means I have to replace the entire ...
3
votes
5answers
122 views

How can I vent a portable air conditioner when there's no window?

My shop does not have central air and does not have operable windows. There is a steel door in the back and cinderblock walls. My landlord is against me cutting a venting hole in either the steel ...
3
votes
3answers
336 views

What material is allowed for a furnace room ceiling material?

What types of material, other than drywall, are acceptable by Ohio HVAC Code for the ceiling of a small furnace room which will: Have return air ducts (only) passing through it to attic space. Butt ...
2
votes
1answer
33 views

Can I use a power gable fan and ceiling louver vents to pull cool air into my house?

I live in L.A. We only have really hot weather 5-10 days a year and it usually cools off at night (outside). I also have a large Gable vent in my attic. (recently added with addition) I would like ...
2
votes
2answers
95 views

How should I wire a Trane air handler & heat strips?

Looking for validation or correction on my understanding of requirements for wiring 5 ton Trane air handler with 20kw heat strips. Of course, I read the label and identified that there are (2) 240v ...
1
vote
1answer
27 views

Good replacement actuator?

I have 2 Belimo actuators that control dampers for A/C ducts in my house that the motor has gone bad on. I can't find much info about the model "LM24-T US" so I think it has been discontinued. I ...
1
vote
1answer
32 views

Sound proofing HVAC ducts

We have an HVAC system in our house where the duct work is all sheet metal with no insulation on the interior of the ducts as all of it is buried under inches of foam roofing insulation. Works great. ...
1
vote
2answers
69 views

How can I use a WeMo controller on a non-standard outlet?

I have an older A/C unit that uses a 6-15p plug. I want to be able to remotely control the unit with a WeMo, but it uses a 5-15r receptacle and plug. The A/C unit says its rated for 208V, and I ...
2
votes
3answers
682 views

Can I cap the air return in my unfinished basement?

I noticed today that there is a massive air return in my unfinished basement. The opening is about 2 meters from the blower, and as large in diameter as the return duct coming from the upstairs. This ...
8
votes
1answer
42k views

Why is my air conditioner tripping the circuit breaker?

Our air conditioner recently stopped blowing out cold air. When I went to check on it, I noticed that the outside unit wasn't coming on. We had had problems with ants in the contacter in the past, ...
3
votes
3answers
536 views

Does my crawl space need venting

I have a crawl space under my main entrance of the house. It's about 3' tall. I added a heat duct because the floor at the entrance was always cold. So my question is do I need to vent the crawl space ...
4
votes
2answers
756 views

ductless AC split systems?

Does anyone have the ductless split AC systems offered by Mitsubishi, etc.? Is installing them a DIY job? Can you share your comments about them, in general? Edit: Inspired by DA01 comment, I'd ...
0
votes
1answer
94 views

How can I determine what grade air filter is appropriate?

I'm trying to figure out what kind of air filter is appropriate for my house. My local home warehouse store stocks over a dozen options. The primary difference between them seems to be Microparticle ...
1
vote
2answers
3k views

How to diagnose a broken Aprilaire humidifier (Model 600)?

I have an Aprilaire Humidifier Model 600 (or maybe 600M) mounted on my furnace. The humidifier is not turning on (i.e. letting water flow over the filter) when the furnace is on. The below images ...
4
votes
2answers
1k views

How well do whole house humidifiers work?

We are moving to an area where it gets cold and snows in the winter. We come from a desert area where it is never very cold except for the dead of winter, and where we use the heater very seldom. We ...
2
votes
1answer
119 views

Is it possible to add a “C” wire to my electric heater?

I bought a Wifi Thermostat but my old thermostat did not have a Common Wire. I can't use any of the swapping the G for the C solutions because I have an electric heater. I was told by Honeywell that I ...
5
votes
3answers
3k views

Should I be concerned about fridge/freezer airflow?

We just recently had the following counter/cabinet system put into our basement family room. After everything was done, I started to get concerned about airflow. The enclosure was built in such a ...
5
votes
7answers
23k views

How can I prevent my HVAC condensate drain line from freezing?

Last night, my heat (forced air) suddenly stopped. Today, a plumber figured out that my heater is 90% efficient, produces lots of condensate, and the drain line had frozen. We went outside and saw ...
7
votes
1answer
103 views

Decrease dust in an old house, forced air

My house was built in 1940. I have noticed the forced air pushes out a lot of dust. This is evident from lint collecting on the bathroom vanity below a vent. It only collects lint during Summer and ...
0
votes
0answers
29 views

What to look for in central air installation?

I'm having an HVAC company install a York central air unit in my house today, and I'm wondering what things I should be looking for in the quality of the installation? Existing York central heating ...
4
votes
2answers
47 views

Solution for fiberglass ducts that have collapsed in basement?

I have two furnaces in my house, one for the basement and one for the rest of the house. I noticed that while using the basement furnace this winter that no air was coming out of any of the basement ...
1
vote
1answer
41 views

What should I do with an unused C wire when installing a thermostat?

Replacing a Carrier programmable with a Honeywell RTH6350D1000. Carrier had blue/gray wire in the C connector. Honeywell does not have a C connector. In install book "Advanced" wiring it says to ...
1
vote
1answer
46 views

what is this unused brown wire in my thermostat wiring?

I replaced an existing Honeywell programmable thermostat with a new Z-wave enabled CT101-L thermostat yesterday. All went well, and the C, W, Y, R and G wires found their proper target connectors. The ...
7
votes
2answers
3k views

What could be causing an orange flame on all appliances?

I have an orange flame in all my gas appliances (gas furnace, gas water heater, and gas stove) and cannot seem to determine the cause. Background So far, I have had the gas company come out. I had ...
1
vote
2answers
1k views

What are my options for venting my oil boiler?

I have a small New Yorker AP-U (480?) boiler that is currently vented to a large flu in my house's chimney. I want to install a wood stove in my house and I'd like to use the chimney to vent it, which ...
3
votes
3answers
20k views

How much less power does a three-phase A\C unit use as apposed to a 220v 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 ...
4
votes
3answers
4k views

Why is my gas furnace vibrating when blowing hot air but not when blowing cold air?

I have a gas furnace. I recently replaced a bad blower motor. At that time I also cleaned out the blower housing and squirrel cage. The AC runs fine with no vibrations or any symptoms of an off ...
1
vote
2answers
299 views

HVAC Duct options in floor joists

I will explain what I would "Ideally" want. I would like the HVAC in the basement ceiling to Not require a soffit. Plumbing seems possible because the holes for the most part will be small enough to ...
4
votes
4answers
6k views

Why would my Goodman gas furnace start but not stay on for more than 2-3 minutes?

I've got a problem with my 15 year old Goodman furnace. It starts w/o problem, inductor begins working, hot surface ignitor lights up and ignites the gas. Then the main blower starts working and the ...
3
votes
2answers
92 views

What is the smell coming through my HVAC system?

If I leave the furnace fan always running for an extended period of time (to circulate and filter the air), when the central AC turns on there is a not-so-fresh smell that is emitted through the ...
1
vote
1answer
38 views

alternative to packaged unit downstairs

House built in 1922. Never had central air. Heated with hot water boiler and rads. 2 stories, 1569 sq ft. Salesman recommended split sys upstairs and packaged sys down. Only appx 22 inch clearance in ...
1
vote
4answers
102 views

My house has electric heat, built in 1969. How can I save $. Are solar panels the way to go, or is there something better out there?

I'm not sure which way to go . My electric bill is nuts. I have a fireplace and it helps, but it only heats one room. Are there any good solar panels on the market? I thought about geothermal but I ...
5
votes
3answers
228 views

How can I improve second floor HVAC performance?

I have a forced air heating and air conditioning system that performs poorly on the second floor: It is way too warm in the summer and a little too cold in the winter. I live in a 1920s masonry row ...
13
votes
2answers
2k views

Can I run a central air conditioner in the winter?

What happens if you run a central air conditioner when it's below freezing outside? Is this expected to work? I know, it sounds crazy, but that's because you don't live in an overheated New York ...
1
vote
3answers
798 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 ...
2
votes
1answer
2k views

How can I prevent heat loss through heater/air conditioner wall units?

HVAC experts out there... I live in Wisconsin and it gets mighty cold here! I have a condo with 2 wall units that are used for both air conditioning and heat. My heat bill in the cold winter months ...
1
vote
1answer
140 views

Why does my shower run out of hot water quickly?

My shower runs out of hot water quickly. Initially the water is perfectly hot, then it starts cooling after a minute or so and we need to adjust the lever to maintain the temperature. Somewhere around ...
0
votes
0answers
20 views

Why does the A/C come on downstairs when heat is on?

I just moved in to a 2-story house. It is zoned upstairs and downstairs. If I turn the downstairs thermostat to OFF and the upstairs to COOL, the HVAC in the attic comes on, the outside compressor ...
0
votes
1answer
44 views

What could be causing a moth ball like smell?

We have a smell like moth balls in bedroom of condo. Moth balls and camphor smell coming from heating unit in bedroom.
3
votes
3answers
9k views

Why is my furnace blower noisy when it starts?

The blower of my furnace makes a loud noise every time it starts. I understand that a large fan and the movement of large amounts of air will produce some noise. What I am puzzled by is the noise that ...
0
votes
0answers
17 views

What could be causing my goodman furnance to not work?

My furnace starts, than the blower motor runs constantly, but trips out on roll out limit switch. The air inlet and outlet lines appear to be unobstructed, but when it shuts down there seems to be ...
1
vote
0answers
121 views

Can't find the circuit board of my HVAC system

I'm trying to install a wireless thermostat for my church building's HVAC system. Currently there is no C wire, so I tried to see where the circuit board was so I could install one. I couldn't find ...
2
votes
2answers
65 views

Can I replace a high limit switch myself?

Thank you for the answer, can I change this myself or do I need to get the HVAC company to do this? I have turned off the breaker in the panel box so that it does not come back on. What is the purpose ...