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

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0
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3answers
460 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
2k 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
619 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
147 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
358 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
45 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
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 ...
0
votes
2answers
191 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
82 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
109 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
1k 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
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 ...
1
vote
2answers
1k 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
1k 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
4k 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
698 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
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 ...
1
vote
0answers
108 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
364 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
130 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
4k 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
99 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
696 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
2k 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
81 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?
2
votes
1answer
128 views

Is my Heat pump and gas furnace installation incorrect?

I moved into a house about 2.5 years ago, and the previous owners had a heat pump installed, together with a gas furnace. Recently I had my furnace repaired (faulty igniter) and the HVAC technician ...
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 ...
3
votes
2answers
356 views

Can 2 - 6“ flex ducts be combined into a single 8” rigid duct

I'm trying to clean up some sloppy HVAC work in my home prior to finishing my basement. I have 2 VERY long 6" flex duct runs coming off the supply master that feeds the great room in my house. Both ...
1
vote
2answers
203 views

At what temperature does a WiFi thermostat stop sending a signal to the router?

I recently purchased and installed a Honeywell WP6500 WiFi thermostat and thanks to Stack Exchange, got it up and running. I have a house in New Hampshire, which I use occasionally during the winter. ...
2
votes
1answer
151 views

Is the furnace undersized?

I have a 2700 sq ft rambler home with cathedral ceilings over a large portion of it - over the hallway, 2 living rooms and kitchen. We replaced the furnace that was installed when the home was built ...
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. ...
4
votes
4answers
525 views

Can I reduce static pressure in one room by adding a vent to an adjoining room?

Our return vent for our hvac is right outside the master bedroom. The master bedroom gets very little airflow with the door shut. It was recommended that we add secondary return duct in the master ...
0
votes
1answer
271 views

Do I need a sleeve for through the wall air conditioner in new construction?

I am about to buy a through the wall A/C unit for a small building, which the builder will frame out for the A/C. Is the framing enough, or do I need to buy a sleeve for A/C?
1
vote
4answers
744 views

Is there a special low temperature thermostat?

I have a gas ceiling mounted furnace for my garage. I want to set my garage at 35-40° F (1-4° C). Is there a special thermostat to control furnace at that low temp? (I've seen one works as low as ...
1
vote
1answer
676 views

Can I convert a window A/C unit in to a pool-water cooled system?

I have an 18,000 BTU A/C unit that blew a compressor last year. Perfect for a small project. I however could not find a professional to help me out, so maybe it's DIYable. I know just about enough ...
6
votes
1answer
978 views

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
1answer
124 views

Bathroom, dryer and central vac - Can any of the exhausts be combined, and can any use the same penetration?

I have these three units within 5 feet of eachother. The place where the bathroom vents to is the only place within reach to have a penetration to outside. My options are to stack these three ...
0
votes
1answer
318 views

Thermostat C-wire replacement using a wall socket?

I have a Filtrete 3M WiFi thermostat. As expected, it takes a C wire, which my apartment doesn't have and the apartment maintenance folks wont' let met wire either. However, there's a wall socket ...
2
votes
1answer
242 views

Breaker box or heat pump problem?

We ran our forced air heat pump today. 15 min. in we noticed it just stopped running. Looking in the breaker panel I could see that the breaker for the heating unit had tripped. When I tried to ...
0
votes
0answers
383 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 ...
7
votes
4answers
6k views

Can I modify the vent from my high efficiency furnace to prevent possible damage to the exterior of my home?

is my high efficiency furnace vent installed properly? I'm based in Toronto, Canada. In some recent cold winter weather, the exhaust is causing a lot of ice buildup on the surrounding brick. To my ...
1
vote
3answers
531 views

Should I leave the fan switch on my thermostat set to fan rather than auto?

I purchased a new Amanda Furnace in Oct'2013. I am told in order to maximize a warm, consistent room temperature I should set the thermostat to the Fan position rather than the Auto position. Does ...
3
votes
2answers
1k views

Is voltage too high in C wire going to thermostat?

I've managed to add a C wire to my thermostat. I then decided to check the voltage between the R and C wires, and find that it read as 27.8 volts, not the 24 volts it was supposed to be. Could this ...
0
votes
1answer
514 views

When should HVAC returns be opened and closed?

My Pennsylvania house was built in the early 90s, has central heat (natural gas) and central A/C, and most rooms have pairs of closable air returns on the wall near the floor and ceiling. I've been ...
0
votes
1answer
32 views

Why isn't my aircon blowing cold air?

I have 2 x 9000Btu split aircon installed in my house three days ago. In fan mode it works properly but when I switch to cooling mode the upper pipe from the outside unit freezes immediately, not cold ...
2
votes
2answers
340 views

Air conditioner not blowing cold air

My HVAC system had a problem during the winter where the blower motor stopped working. I got a HVAC tech to come out and replace it. However, now that it's hot again, the cooling system is still ...