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

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0
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1answer
75 views

AC unit (turned on year round) leaves so much ice in the blower causing no cooling (pic included)

My mother has asthma and tells me she needs the AC on almost year round. The AC unit is outside the condo we own, and it connects to the coils in the heater/ventilation system. We are experiencing ...
0
votes
2answers
117 views

What size A/C unit should I install?

currently using a Goodman 24000 BTU Central air, installed in '96. it is starting to cost too much because of leakage of refrigerant. I did the size calculator thing and it recommends a 30000 BTU ...
0
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0answers
117 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 ...
1
vote
3answers
102 views

Swapping out circuit board on York AC?

I have a York AC unit where the circuit board is shot, so I bought a replacement circuit board (same model). The model number for the board is 031-00251C. Pictures of old circuit board: ...
1
vote
2answers
554 views

What could be causing my A/C not to come on?

I had a thermostat get hot and smell, replaced thermostat. Still not working found fuse on control board blown replaced fuse. Lights on control board indicate no problems. Replaced 18/5 cable from ...
1
vote
1answer
860 views

How should I evaluate my central A/C to see if it's working properly?

I was once told by a service tech that they evaluate how well the system is performing based on temperature difference between the the return and supply sides. On our first really warm day (80F+), I ...
4
votes
7answers
6k views

Would putting a sprinkler on my roof help cool my home?

Anyone ever put a sprinkler on your roof to help out your A/C on unusually hot days? Just wondering if it helps.
1
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2answers
317 views

Is a little ice on the cooling coils ok?

This is our first summer in a new house which has central air. It was a bit hotter today than normal so the AC was running for a long time. After awhile we noticed the airflow stopped because the ...
3
votes
4answers
7k views

How can I connect two indoor ductless A/C's to one compressor?

I have one Hitachi i-clean split AC 2ton unit installed in my home. I want to connect another indoor ductless unit to the already installed outdoor compressor. I only need to use one indoor unit at a ...
0
votes
3answers
204 views

A/C Runs non-stop and shuts down without reaching desired temp

I have had a repair man out 4 times and he says he can't find anything wrong with the unit. I cannot even feel air coming out of the diffusers unless I climb on a chair and put my hand right next to ...
15
votes
4answers
13k views

Why don't programmable thermostats automatically switch between “Cool” and “Heat”?

While I can set my house to be a particular temperature, I still have to manually switch it between "Heat" and "Cool" mode, and this seems to be true of every thermostat (programmable or not) that ...
1
vote
1answer
958 views

What causes a HVAC control transformer to overheat?

I recently replaced my 24 volt HVAC control transformer. The outside unit started up including the air handler and ran for maybe 10 minutes. After the units shut down I noticed that the transformer ...
8
votes
4answers
739 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 ...
4
votes
2answers
2k views

What are these two pipes coming out of the house?

I am trying to figure out the purpose of a couple of pipes that are currently coming out of the house. First, a couple of notes: One-story house. HVAC system is in the attic. It is winter here. ...
0
votes
1answer
152 views

Can I fill this AC line inlet with expanding foam?

I think the PVC inlet for my AC lines is a possible entryway for mice getting into my attic. Is there any reason I shouldn't fill it with expanding foam to seal it off? Or is there a better, less ...
0
votes
3answers
101 views

Will high efficiency furnace plumbing lead to cold air entering the house?

At the outside wall of my house I can see two white PVC round tubes/pipes, I understand one is for sucking air from outside, and one is for furnace blowing warm air to outside - correct? We are ...
1
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0answers
70 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 ...
0
votes
2answers
107 views

how do I keep leaves and foreign objects out of the top of my a/c unit?

Is it possible to make a lid that is light enough for the air coming off the fan to raise it attached with hinges so it drops back down when not in use. This would keep debris from getting inside, yet ...
4
votes
5answers
23k views

Should I insulate air conditioner coolant pipes?

I recently replaced some rotted insulation on the coolant pipe that runs out of my AC unit and into the evaporator in my house. When cleaning inside the actual AC unit itself I noticed that the ...
0
votes
0answers
30 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
108 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
1answer
299 views

How well does a single A\C unit provide 2 zone cooling?

My 2,900 square foot house currently has two separate AC systems (one upstairs, one downstairs). They're both very old and need to be replaced. One of the four HVAC salesman that provided quotes ...
0
votes
3answers
588 views

Can I wire a Bathroom Fan to two Switches in Parallel?

I want to control a bathroom exhaust fan with a wall timer, and a 24 vac relay. Basically both switches would be wired in parallel. Is this safe to do?
9
votes
5answers
4k views

Why won't HVAC supply stores sell directly to the public?

I am quite shocked that every store in my very large metropolitan area that sells HVAC supplies requires purchasers to have HVAC contractors license. Which makes it very difficult for a very ...
0
votes
2answers
784 views

Can I install whole house humidifier in AC ducting?

Just grabbed 2 Honeywell whole house humidifiers: HE360A1075. It's the best model Lowes has and recommends. I have 3 floors and a basement in an old (1890s) victorian house. We have cast iron ...
1
vote
1answer
1k views

Is it possible to use my window A/C unit without actually installing it in the wall?

So, here's the dilemma. I want to install a window unit in my garage. I know how to do this, but my wife isn't supportive of the idea because we are trying to sell the house currently. Anyways, ...
1
vote
1answer
195 views

How to maintain temp for always cold office in finished Basement

I work out of my home in an office in our finished basement. The room is always cold whether it's the middle of winter or the middle of summer. I often run a cheap space heater (especially) in the ...
0
votes
1answer
1k views

Need help running and connecting a 'C' wire to my new thermostat [duplicate]

I have a Laars gas boiler that has 3 heating zones; basement, 1st floor, and 2nd floor. I want to replace the old mercury honeywell tstats on the 1st and 2nd floor with newer honeywell RTH9580 wifi ...
0
votes
1answer
413 views

How should I attach a C wire on my chromalox boiler?

I have a chromalox canada boiler model EDB-2. Recently I purchased a wireless honeywell transponder and thermostat, and am trying to install them. I currently have W and R wires but am missing a ...
0
votes
3answers
51 views

Can forced central air be retrofitted with central humdifier?

Several homes I'm considering have central air conditioners, but radiators or baseboard heaters. Is it possible to use the A/C ductwork to provide humidity to the home? I assume most central ...
1
vote
0answers
27 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 ...
0
votes
2answers
353 views

How to Calibrate a Make-Up-Air Controller?

My home is equipped with a make-up air line intended to bring some outside air to mix it with indoors air prior conditioning by the furnace. I am not sure why this is necessary but my question is ...
4
votes
2answers
85 views

Resources for designing new HVAC [closed]

Our house is a bungalow with full basement and is currently heated via electrical baseboard heaters in every room. I'm converting this to a central air system heated by a gas furnace, and possibly ...
0
votes
1answer
125 views

Should I remove existing drywall before framing a wall around HVAC ducts?

My friend has soft AC ductwork running up an interior wall. He wants to build a wall around it to hide the ductwork. My idea is to pack out the wall by nailing in framing between the ductwork right ...
0
votes
1answer
2k views

Quieting cold air return vent

My gas furnace is in a dedicated "closet" inside the utility room. The closest cold air return is about 5' away (laterally) in the ceiling of the hallway right by the bedrooms. When the furnace ...
0
votes
0answers
97 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 ...
1
vote
2answers
3k 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
4answers
2k views

How to fit 4" rigid aluminum duct vent in between walls when there is an angle brace?

I want to do what these people have done here: The problem is I have bracing going diagonally and it is not leaving enough space for the 4" aluminum duct vent. Can I saw the bracing off for the ...
0
votes
1answer
5k views

Wireless Thermostat C-Wire Substitute

I've read How can I add a "C" wire to my thermostat? and checked out the Venstar Add-A-Wire Accessory. I've watched Honeywell's YouTube video on "DIY Wi-Fi Thermostat Substitute G-Wire for C-Wire," ...
1
vote
1answer
806 views

How to wire a new Honeywell RTF6580WF thermostat to replace a Chronotherm IV?

I have an old Honeywell Chronotherm IV thermostat that I am trying to replace with a Honeywell RTF6580WF wifi thermostat. I have a gas furnace and an air conditioner. Wiring for Chronotherm IV ...
0
votes
0answers
68 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
53 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 ...
1
vote
0answers
125 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 ...
2
votes
2answers
400 views

Is Flex Duct Safe To Use In A Crawl Space?

The home I purchased has a crawlspace below an addition that was put on to the original structure. The HVAC contractor that did the work ran 2 long runs of flex-duct to the 2 registers in the room of ...
0
votes
1answer
420 views

I have just reset furnace due to a trouble code, what should I monitor or re-do over the next few days?

My furnace was throwing a trouble code. The code was 31 and for my manufacturer (Bryant) and others thats is a pressure switch code. I was able to resolve this code and get my heat back on simply by ...
7
votes
2answers
5k views

Why are almost all of my house's HVAC floor registers placed near exterior windows?

My current house is a single story built over a crawlspace and all the HVAC registers are in the floor. In all of the larger rooms, at least one (and usually more) register was placed near an exterior ...
0
votes
1answer
200 views

How can I prevent my furnace exhaust pipe from freezing?

My furnace keeps on turning off because my air intake freezes. The reason it freezes up is because my neighbors exhaust vent blows directly on it. What can I do to prevent this?
1
vote
1answer
2k views

Which way does the air flow through my furnace?

Below is my furnace and I need to change the filter however I am unsure which way is the airflow direction. Red or Blue?
1
vote
4answers
3k views

How can I calculate the power consumption of an A/C unit?

I have an AC unit with the following specs: Cooling Capacity: 1260 kcal/h, 1.47kW, 5000 Btu/h Fan Motor Power: 0.034 kW Current: 0.155 A My question is how much power does this unit actually ...
0
votes
1answer
86 views

Does HVAC lineset need to be grounded?

My HVAC contractor says the installation of the line set between the air handler and the condenser outside is complete but he has not grounded the lines. Do HVAC copper pipes need to be grounded?