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

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0
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1answer
72 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?
0
votes
1answer
806 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
245 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?
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2answers
117 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 ...
1
vote
1answer
106 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 ...
2
votes
1answer
183 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
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0answers
184 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 ...
1
vote
3answers
466 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 ...
6
votes
1answer
418 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 ...
0
votes
1answer
236 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
30 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 ...
3
votes
2answers
2k views

What kind of wall switch is needed for a natural gas fireplace to ignite consistently?

When we moved in, our natural gas fireplace worked well: Flick the switch & it would ignite. Years later, it started acting erratically: Sometimes, the switch worked, other times, no luck. We'd ...
0
votes
1answer
128 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 ...
3
votes
1answer
197 views

180º/gooseneck/u-shaped cold air return?

I am in the planning stages of moving a cold air return from an inconvenient spot in the floor to a nearby wall. The basic plan is to open up the wall on both sides (cutting one stud and framing in a ...
0
votes
1answer
101 views

What is this fabric tape made out of?

Any ideas what is this fabric tape on my cool air return ductwork? High res close-up Some of it is separating or worse falling off of the duct work on the cool air return to my forced-air gas ...
0
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3answers
2k views

How can I modify a 4 wire thermostat to a new thermostat requiring c wire?

I attempted to replace my thermostat with a fancy new Trane z-wave enabled model. To my dismay my home was only wired with a 4 wire setup with no 5 hidden in the bundle. I followed Insx on the web ...
1
vote
1answer
137 views

Propane HVAC system - convert to use wood burning stove?

is it possible to remove the propane part of the HVAC and replace it with a wood burning stove? If so what would I have to change - eg the chimney etc etc?
0
votes
0answers
35 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
1answer
635 views

How do I connect a WiFi thermostat to my furnace's primary control?

I would like to install a Honeywell WiFi controlled thermostat to connect to a Honeywell R7184U primary control. My question concerns the "C" wire. The R7184 has the terminals labeled 1, 2, 3 and 4 ...
0
votes
1answer
161 views

I just had a heat pump installed. I had central air already so the duct work was there already for a/c. Should my vents in the ceiling be changed?

One person told me I need to change my Registers on the first floor that are in the ceiling because the house was set up for air not heat. They say the Registers I have keep the cold air going a ...
2
votes
2answers
306 views

Furnace flashing 4 times (Ducane)

My Ducane furnace flashes 4 times, runs for 5 minutes, and then the burner goes off. When the limit switch is jumped it runs good. What needs to be changed here?
0
votes
1answer
601 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 ...
1
vote
2answers
2k views

Controlling separate heat and AC devices from a single thermostat

I have hydronic radiator heat powered by a gas furnace situated in one mechanical room of my house and a currently being installed central AC whose air handler is situated in another mechanical room ...
4
votes
1answer
227 views

How can I determine if my HVAC system has features which are not currently wired to my thermostat?

I recently upgraded to a Nest Thermostat. This new thermostat supports many more terminals and features than my previous thermostat. My old thermostat had the basic terminals; G,R,C,Y, and W. I am ...
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vote
3answers
96 views

can I install a new thermostat by just turning off the power instead of turining off the circuit breaker?

Can I install a new thermostat by just turning the power off at the servicemen's switch, instead of at the breaker?
1
vote
2answers
2k views

Can a boiler water feed / pressure relief valve be repaired?

I am a homeowner trying to troubleshoot my hot water boiler system (Winkler Gas Boiler). I noticed recently that my boiler is reading zero pressure. The combination fill & pressure relief valve ...
0
votes
1answer
3k 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," ...
7
votes
4answers
4k 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 ...
2
votes
2answers
141 views

How to measure air flow coming out of registers?

As my contractors finish installing ductwork and the air handler for my central AC system, I would like to have a measure of how many CFMs come out of each register, as a function of how the system is ...
0
votes
1answer
265 views

Can I use a heat gun to melt the Ice from the external part of split ductless system?

I've got a Mitsubishi Mr. Slim split ductless system in the "mother-in-law" suite of my house. There are 3 wall units connected to it, one in the front room, one in the bedroom, and one in the ...
0
votes
1answer
307 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
1answer
126 views

Is it OK that my AC is making squeaking and rattling noises?

Just want to get some initial thoughts before the repairman comes. I have a 3 year old 2.5 ton Goodman AC unit. I set the temperature to 74°F last night (AC) and woke up to a nice and chilly ...
0
votes
1answer
87 views

I have both a natural gas burner with baseboard heat and 6 Mitsubishi Mr. Slim units. Which would be less expensive to use for heating my house?

I just purchased my house a few months ago. The house has both a 2 zone natural gas burner with baseboards for heat and 6 Mitsubishi Mr. Slim units that I can use for either A/C or heat. I am not sure ...
0
votes
0answers
145 views

How do i connect the common c wire in a carrier air handler? [on hold]

I need help in determining where to hook up the common c wire for my new thermostat. The carrier air handler appears to be a little more complicated than others.
0
votes
0answers
109 views

Spiral pipe size vs. CFM for AC

My AC contractor just brought some 8 and some 6 inch spiral pipe to install tomorrow. I do not trust him nor do I trust a single contractor out there, hence posting here to confirm. I am getting a 3 ...
0
votes
1answer
68 views

How can we protect this furnace from environmental conditions?

I was recently asked to look over the utility closet of a friend, and several things I saw looked very concerning, from an energy-efficiency standpoint. This closet is approximate 3' x 6', and is in ...
0
votes
2answers
302 views

HVAC air handler with a built-in humidifier

I am in the process of choosing an air handler to use only for AC. I plan to keep radiant heat. However, in the winter, I would like to use the AC system to blow humidified air to compensate for the ...
0
votes
3answers
545 views

extra thermostat, electric dampers and 1 furnace [duplicate]

I have a problem similar to others that have posted: balancing heating/cooling throughout the house. I have already played with adjusting the vent's air flow as well as the manual dampers in the ...
1
vote
1answer
34 views

Testing AC ductwork

I am about to bring in a contractor to install central AC in my house. I am in the final stage of a rather comprehensive remodeling effort, all of which was done either by me directly (cca. 85%) or ...
0
votes
1answer
121 views

Legal requirements regarding 100% asbestos duct work [closed]

I am renting a condo. After starting the heater, dusty air came out of the registers, so I called out a company to clean the ducts. They verified the ducts are 100% asbestos and cannot be cleaned. ...
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 ...
3
votes
2answers
831 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 ...
1
vote
1answer
757 views

Is it okay to connect a round supply duct directly to an air handler?

I removed all of my existing duct work that was designed as a radial system with a sheet metal rectangular plenum with very long flex runs poorly attached. I am replacing my system with all round ...
0
votes
2answers
448 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 ...
0
votes
0answers
144 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 ...
1
vote
1answer
1k views

How can I figure out why the low voltage furnace fuse blows on heat but not cool?

I have a Tempstar Model NTC6100KFG1 gas furnace. Furnace was working fine through the summer blowing the AC. It's been off for a month or two as we've been changing seasons here. When I went to turn ...
0
votes
2answers
6k views

What size breaker and wire do I need for central air conditioning?

I am getting ready to hang drywall in my basement but before I do that, I need to run wire from the main panel upstairs to the future location of the central AC furnace through the basement ceiling ...
1
vote
1answer
722 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 ...
2
votes
2answers
6k views

How do I identify the C terminal on my HVAC?

How do I identify the C terminal on an HVAC, furnace, or boiler? If the terminals don't have a screw labeled C what should I look for on the wiring diagram? What steps should I take if a wiring ...
3
votes
2answers
661 views

Can I attach a HEPA filter to the HVAC outlet?

I am currently living in China and want to improve the indoor air-quality. We have a Hitachi R410A HVAC. All the room in the house are controlled separately. Just to make it clear up front, I am not a ...