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

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2
votes
1answer
110 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 ...
2
votes
1answer
143 views

How do I connect a C wire to an Utica PEG112CDE steam boiler?

I want to upgrade my old mercury thermostat that I currently have to a newer programmable thermostat. This little DIY project is for my first late 1920's home that I recently purchased. I currently ...
6
votes
0answers
69 views

Does anyone have experience with small heat-recovery air exchangers?

I know there are units made which are supposed to be sized for use in a residential kitchen, as a more efficient replacement for the usual vent hood (bring air in to replace air blown out, but ...
2
votes
0answers
218 views

How can I insulate and elevate an A/C line set on a flat rubber roof?

The Scenario An apartment building with a flat black rubber roof. The A/C condenser is on a platform on the roof with an air handler inside the unit. The line set runs across the roof for about 20 ...
2
votes
0answers
80 views

Should I install the jumper on my new limit control?

I needed to replace fan and limit control (White-Rodgers, model 5D51-35), because the fan switch was broken (fan would constantly run) and heat would not stay on. I took a picture of the control, ...
2
votes
0answers
531 views

What are good Relative Humidity and Temperature settings on an MHRV and are the settings related?

I need to configure the threshold Relative Humidity and Temperature settings on an whole house MHRV system. The way the system works is that if the RH threshold is exceeded the system increases the ...
1
vote
0answers
41 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
0answers
15 views

Why is my hydro kinetics system blowing out cold air?

I have a hydro kinetics system that is blowing out cool air when set to heat. Thermostat was replaced when I bought the house a year ago so I don't think that's the issue. Toggle switch is set to ...
1
vote
0answers
208 views

Why is my furnace blower running at low speed?

My Payne gas furnace (PG8UAA 42091) automatically shuts down after it lights and burns for two minutes. It then gives a 33 fault code. I've done some research and some testing and have narrowed the ...
1
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0answers
66 views

Dust reduction and removal?

I have a room with west facing windows (I dont think the direction bears any importance to this question), but for some reason this room seems to accumulate dust on surfaces a lot faster than other ...
1
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0answers
24 views

How can I reduce the noise from an HE boiler vent?

I have a HE boiler that is direct vented out the side of my house on the neighbors side, they find the 'roar' of the exhaust to be very annoying. Have anyone tried troubleshooting these to ...
1
vote
0answers
109 views

How can I install a furnace register in a kitchen-cabinet toe kick?

I'm planning to install new kitchen cabinets. I'll be covering up the kitchen's existing sidewall diffuser with new cabinets, so I'd like to relocate it to a new register in the toe kick of the sink ...
1
vote
0answers
786 views

How can I tell if my bathroom ceiling vent is working properly?

Seems to take the vent forever to clear shower vapor from room. I purchased a vent that had a good rating. It is vented to the outside. How do I know if it is working properly and actually venting to ...
1
vote
0answers
682 views

Reducing air conditioner compressor vibration noise

I have a two year old Carrier air conditioner with an outdoor condenser. The condenser sits on a plastic pad on the side of my house, and I have two--one for downstairs and one for upstairs. ...
1
vote
0answers
83 views

How do I troubleshoot my central A/C?

It's 79 outside right now. It's been running for hours and it's remaining 79 inside. I'm in a brand new 2 story home in Monroe, OH. It has rained a lot recently but I just feel like it should be ...
1
vote
0answers
86 views

Why doesn't my A/C get power when using the alternate C-wire thermostat hook-up method?

I changed my old Honeywell thermostat for a new Honeywell WiFi thermostat. I installed it just as the directions stated. I used the alternate C-wire method as the old unit did not have one. ...
1
vote
0answers
1k views

How do I size a wall sleeve for a through-the-wall air conditioner?

We are shopping for a through-the-wall air conditioner. We do not currently have a hole in the wall with a sleeve in it. We are trying to figure out what sleeve to buy. The air conditioner we like ...
1
vote
0answers
727 views

What's causing my draft inducer to stay on?

I have a new, 3-year old, high-efficiency, gas furnace in my home. I recently realized that my draft inducer, which normally kicks on before the burners and before the main blower, is not stopping. ...
1
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0answers
678 views

How can I properly drain heatpump condensate?

I have a heat pump in the attic That drains to the ground outside two floors below. I naively added a hose fitting so I could redirect the water where I wanted it, slightly up hill. This created a ...
0
votes
0answers
11 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
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0answers
22 views

Can ultrasonic humidifiers be used in a bypass setup for a whole house humidifier?

My home is about 3000sqft, with lots of high ceilings. I'm having trouble keeping the relative humidity up in the winter. When it gets down to 10F outside, the RH drops down as low as 25%. This is ...
0
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0answers
16 views

Whole house humidifier - can you use a steam/mist with a heat pump?

Just moved into my new house and first time with an electric furnace and forced air with a heat pump (rheem) - and immediately we noticed that our skin is super dry and cracking. I was looking into ...
0
votes
0answers
24 views

HVAC ducts ready for finished basement?

I'm starting to finish my basement. Before I do so, I want to be sure the ductwork is sufficient to keep it warm during Colorado winters. The basement was finished when we moved in, but gross, so we ...
0
votes
0answers
33 views

Can changing the fan speed on a forced air heating system reduce the sound heard in each room?

We recently converted to gas heat. Now, when the heat turns on, there is very loud blowing in almost every room. My Carrier Infinity fan speed is set to "Auto." I was told there is nothing to do ...
0
votes
0answers
23 views

Why did my central heat shut down?

I did maintenance and turned on the electric heater switch on thermostat to Central Unit. It came on just fine and warmed up the house and shut off automatically. But it never came on again. The a/c ...
0
votes
0answers
9 views

Should my Trane dual zone XB14 be short cycling?

I have a 2 yr old Trane zone dual system and it is short cycling whenever I run the ac side, I called the HVAC installer and he said that is noraml due to the fact that the temperatur is 72 degrees ...
0
votes
0answers
39 views

What could cause the heat side of our split pack heating/air unit to stop working?

Our heat side of our split pack unit (runs on propane) come on and will runs little bit but then won't come on again. We can turn it off for a while and then it will run again. What could be the ...
0
votes
0answers
91 views

possible HVAC Selector Wiring Solution?

I moved into my current home last winter. This house has an old zone controller MasterTrol Mark V model Mabs-V-3. UPDATE: just found that all wires connected to M? end nowhere. So I remove all the ...
0
votes
0answers
24 views

Electric HVAC unit runs and stops randomly

I just turned on my heating unit for the season and it seems to be running and stopping intermittently. I'm not sure if this something to be concerned. This happened last season as well and I called ...
0
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0answers
35 views

Central AC is Icing up, but not cooling my house

My central air conditioner isn't cooling like it used to. I noticed that the refrigerant lines entering the evaporator coil in the plenum were icing up. What might the problem be?
0
votes
0answers
32 views

Why is my A/C's breaker tripping all the others?

I noticed the A/C wasn't coming on - even the outside compressor - so I checked the breaker and the two switches that the A/C is on were tripped. At this point no other breaker was affected. I went to ...
0
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0answers
210 views

Furnace not working properly with digital thermostat

I have been attempting to use several different types of digital thermostats to replace my old mercury thermostat, however none of them are able to control the furnace properly. All of them are able ...
0
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0answers
37 views

Which should I do first? replacing furnace or resurfacing concrete floor?

I'm going to get two things done in my basement soon (by hiring professionals), but I'm wondering what the right order of operations is. One task is to replace the gas furnace that sits near the ...
0
votes
0answers
80 views

Thermostat replacement

My old thermostat is a carrier t-stat and has a jumper wire between o/w2* and L I am upgrading to a honeywell wifi t-stat, should I install the same jumper wire on the new thermostat? I have an ...
0
votes
0answers
91 views

How can I install a floor register in bathroom

I need to install a floor register in my bathroom (which I am currently remodeling). I plan to put one into the floor under the window where it used to be. The old register came up through the floor ...
0
votes
0answers
28 views

Is my vent cap big enough for my vent hood?

I have installed a 900 CFM island vent hood. It works properly, but it doesn't vent as quickly as I would expect. The ducting is only 18" and straight out (and up) through the roof, so that's not ...
0
votes
0answers
103 views

What could be causing our air conditioner circuit breaker to keep tripping?

Our air conditioner circuit breaker marked "AC", is tripping frequently after the AC unit works for a while. Sometimes as long as an hour or more and, sometimes as short as few minutes. We were told ...
0
votes
0answers
78 views

How can I repair my imitation fire coal bed?

The coal bed beneath my imitation gas fire has cracked. (It is vermiculite type of material) The part is obsolete, so can it be repaired or can I get hold of a block that I could shape or sculpt to ...
0
votes
0answers
62 views

What steps are required to convert R-22 Freon to a new R-410A Puron system?

I am house hunting in Houston. Every 2000-2004 house we've seen so far uses old A/C Unit and coils for R-22 Freon and not the newer R-410A Puron. Reference: ...
0
votes
0answers
47 views

Can I rerpalace only the booster motor on a booster assembly for DGAT furnace?

This furnace did not have a problem until the service man oiled the booster motor recently. 1-2 weeks later the booster motor bearing began squealing, and I found 2 tbs. of oil below the motor. The ...
0
votes
0answers
101 views

Why is my heat not shutting off at the set temperature?

When I turn the heat on on my central heat and air unit, the heat came on then continued to run getting really hot. It would not shut off unless I turned from auto to on then back. Sometimes I had to ...
0
votes
0answers
24 views

Goodman heat pump in SC freezing up at least monthly

Identical units in new neighborhood but my unit is the one freezing up excessively and has shut down completely. HVAC installer says everything is normal but when your heat shuts off until you ...
0
votes
0answers
81 views

Diagnosing boiler problem. Strange noise and pressure released

Woke up to a loud almost grinding noise coming from all the radiators/pips in my hot water heating system. It's intermittent, every few seconds but the system is generally running louder than normal. ...
0
votes
0answers
398 views

Why would said gas furnace keep shutting off?

Seems that I have a gas furnace that is having some sort of heat/air sensing issue. Basically it shuts off after running for a minute or two. But if I remove the top plate of the furnace itself it ...
0
votes
0answers
38 views

How do I fix a blower fan snap disc that opens too soon?

My fan limit thermodisc opens too soon and shuts the fan motor down after the gas burners ignite and runs for about 2 minutes. I replaced the limit switch and still have the same problem. How do I ...
0
votes
0answers
172 views

Is it possible to insulate existing ducts without removing drywall?

My second story is always warmer in the summer and cooler in the winter than the ground floor. I've had the ducts cleaned and sealed and I've also adjusted the blower motor speed. It occurs to me that ...
0
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0answers
122 views

AC won't turn on after replacing thermostat batteries

we replaced the batteries on our thermostat after they began flashing for a few minutes. We'd been using the heater up to that point. After replacing the batteries, the heater does not turn on ...
0
votes
0answers
33 views

How can I determine if a valve complies to MSS?

How to know if the valve complies to Manufacturers Standardization Society (MSS) or not? I want to approve a valve for an HVAC project, but I don't know how.
0
votes
0answers
215 views

Why isn't water running through our radiators?

We had a plumber in today to bleed our rads. He also changed the batteries on the thermostat and fiddled around with the boiler. Since he left the temperature has dropped dramatically and he's refused ...
0
votes
0answers
84 views

I have no furnace, only electric blowing heaters. How do I get ventilation?

I have a 100 years old building with a store on the main floor. Since the building was built over 100 years old there is no ducting whatsoever. There is also no furnace. In the summer we just hook ...