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

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3
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2answers
254 views

How to address loud cold air return

The cold air return on my forced air furnace is too loud. While it is is tolerable, there is a noticeable sound of rushing air when the furnace is running (not a whistling sound, just a blowing sound)....
1
vote
3answers
119 views

Leakage in my pipes, how to densify/seal?

I've never built with pipes before so maybe I'd need some general advice regarding leakage. On a specific note, I've built a system (see picture) where it leaks practically everywhere. I've sealed it ...
1
vote
1answer
88 views

HVAC - Circuit Board Fuse blows on AC Switch

I have a Honeywell System. Back in November of 2014, I replaced the Circuit Board with one by Honeywell from Amazon (1014460). The blower motor was replaced over 2 years ago. Last month, I have ...
1
vote
2answers
113 views

HVAC technician can't do ductwork because of zoning limitations?

I'm doing a renovation on an unfinished area, size about 350 sqft. During my rough framing/electrical/mechanical phase inspection, my county inspector didn't mind the idea of tapping into the ...
0
votes
1answer
33 views

Why doesn't the extra C wire work when hooking up WiFi thermostat?

My existing thermostat has an extra 5th wire. It's blue. We used that as the C wire. We have forced hot air so we checked the furnace and it has all the wires hooked into a clip that plugs in. It has ...
1
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3answers
514 views

How to insulate register boot?

The county inspector dinged me on a couple of things for my bonus room renovation. One of these things is wrapping the register boots (endpoints) in insulation. I've seen registers with this ...
0
votes
1answer
32 views

how to measure CFM in digital animometer [closed]

dear friends how to measure CFM in digital anemometer and tell how its calculated in both practical and theoretical
7
votes
2answers
1k views

Should I bypass a thermal cut-off switch on my oil furnace?

My thermal cut-off switch for my oil furnace blew and my neighbor replaced it until a tech could come out and check it when I had my cleaning. The switch blew again and the furnace tech bypassed the ...
0
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2answers
80 views

Bedroom 10 degrees colder than rest of floor!

I'm at my wits end. I just moved into a new (for me) 2 story house (1998) that has some weird heating issues. The house is about 3200 sqft the upstairs is heated by a furnace located in the attic. its ...
0
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1answer
40 views

Why does my nat gas furnace pilot light stay lit at normat temp setting, but goes out when I bump the temp up a couple degrees?

Recently the gas company replaced our meter and thermocouple. After they left, the pilot light kept going out randomly. 4 techs came over a 3 day period and could not diagnose except to reassure ...
0
votes
1answer
78 views

Wiring for New Thermostat

I just bought new programmable z-wave thermostats (Honeywell TH8320ZW). I thought I had the wired correctly, but I woke up to a pretty chilly house this morning. The fan is working, but it seems to ...
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0answers
22 views

Furnace pilot goes out after furnace runs

I have a Cozy standup wall unit furnace CF553D-H. When the thermostat calls for heat it starts and will power up the ought both fan levels ... Then as it reaches temp and starts the cool down, the ...
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vote
3answers
100 views

Furnace turns off power to the thermostat

When my natural gas furnace is running for a while and it gets too hot, the limit switch turns off the burner. When it does this, the power also gets cut to my thermostat. This causes the thermostat ...
0
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2answers
56 views

Installing Honeywell Wifi on Ruud Furnace with G wire replacement

trying to install RTH9580. My thermostat has only 4 wires so I am trying to substitute the G wire instead of C wire. On the furnace I put a jumper between Y and G wires and moved G wire to C wire ...
0
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2answers
42 views

Is there a way to measure the output of a single HVAC vent?

As inspired by this previous question, is there a method or device used to measure the output of a single HVAC vent or the output of a single room? I'm imagining some sort of hood device that could ...
2
votes
2answers
104 views

How can I get better HVAC airflow?

I recently purchased my house which was a new construction. Several of the vents are getting poor airflow but the installation company simply said it was normal but I suspect otherwise. I recently ...
1
vote
4answers
90 views

Furnace Tries 2 or 3 times before staying on until reaching set temperature

I have noticed my furnace will cut the exhaust fan before lighting or sometimes start heating for a few minutes then stop. A few minutes later it tries again and will stay on until reaching the ...
1
vote
1answer
42 views

Limit switch doesn't function on oil furnace

my limit switch on my oil furnace does not shut off the burner when it hits the limit.I replaced the limit twice maybe I had a bad one still no luck . While furnace was running I took the thermostat ...
1
vote
3answers
71 views

Duct sizing impact on flow

We have a ranch with a wood fireplace in the living room. It's fantastic at heating the main living area, but the bedrooms down the hall get left in the cold. I'm going to install insulated flexible ...
0
votes
1answer
23 views

Payne/Carrier furnace pilot problem

The furnace blower started running constantly and I noticed there was cold air coming fromm the vents and not heat. I have a Payne (Carrier) furnace. The spark gap igniter was not throwing a spark ...
0
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0answers
18 views

Lenox home AC unit doesn't turn on at all, I need help

If you try to turn the out side unit from out it will turn on , but from inside it doesn't do anything. I check the fuse in the inside unit is good, check the overflow it looks good. I just can't ...
1
vote
2answers
340 views

Can I connect the R and C wires directly to the HVAC transformer?

I have a Rheem furnace and a Ecobee3 smart thermostat. I'm having a problem where the Ecobee3 randomly loses power and reboots. I've traced this back to the control board (IFC) inside the HVAC unit. I ...
1
vote
1answer
17 views

Goodman furnance Air pressure switch - faulty?

I have at least a 10 year old Goodman gas Furnance. The past couple of days the burner and blower did not come on. I do not see any indicator lights come on. The inducer comes on, but nothing else. ...
0
votes
3answers
106 views

What steps are needed before brazing attic a/c copper tubing with a leak?

Yesterday I discovered water stains on one of the air ducts in my house. I went up the attic and saw that a copper pipe cool to the touch which seems to be linked to the condenser? had a pin point ...
0
votes
0answers
62 views

calculating the size for an a/c compressor

I have been looking around and can't seem to find this anywhere. I am trying to figure out how to size an a/c compressor to an a/c system. Unfortunately I have not sized out the system, so there isn't ...
2
votes
1answer
358 views

Want to add a WIFI thermostat, but no 'C' wire… only 2 wires to each thermo

i have a 5 zone radiant floor, oil fired heating system. Each thermostat only has 2 wires running to it. i have a TACO SR506 switching relay that receives the wires from each thermostat and controls ...
1
vote
1answer
82 views

How to power Honeywell wifi thermostat with external transformer

I want to install A Honeywell RTH 6580 WF thermostat in my garage for heat only . My heater is a simple LP gas, hanging unit heater; heat only and my thermostat has two wires labeled W and R . I ...
2
votes
2answers
59 views

How to install small damper in a duct?

I need to install a Honeywell 10x10 damper into a 11x11 duct. Options that I came up with: build an adapter to reduce duct to 10x10 (alternatively I can use 12x12 damper and build adapter to ...
1
vote
1answer
37 views

Wintertime and AC line frosted & dripping water in basement?

One line IS insulated in the exposed basement ceiling, so I am supposing this frosted & dripping line is the smaller return line? Have a dehumidifier running but the problem remains. What can I do ...
1
vote
2answers
116 views

Optimizing heating in a heat-pump + electric resistive system

Outside, I have a LENNOX 13hpx-036-230-17 compressor: Inside, the air handler is a LENNOX CBX25UH-036-230-1: The air handler lists 36,000 BTUH cooling capacity, with r410a at 450psi, cust part #...
0
votes
0answers
63 views

Liquid line freeze up

Why would the liquid line on residential air conditioner freeze up during winter months, even though compressor isn't running? Have shut breaker off to assure outdoor unit isn't coming on.
2
votes
3answers
528 views

Would it be a bad idea to use two air filters?

The filter in our central air/heat is directly under the unit and very difficult to replace filters. Even though we use 3 month filters, we replace them monthly due to pet hair/dander. It's a pain to ...
1
vote
2answers
310 views

How does fresh air get inside a house with central heating other than through cracks of door or window on a cold winter day

I'm not sure how fresh air, or oxygen, gets inside my house other than through cracks of window or door on a cold winter day when the central heating system is on. I have a pipe that is coming from ...
1
vote
2answers
37 views

Gas Pilots going out

I have a unique problem with the gas pilots in my house. They all seem to be going out. One day I found both pilots in my fireplaces out. Didn't think much of it. I then found the pilot on my hot ...
0
votes
1answer
43 views

Replacement part for coal stove blower rheostat

I have an Alaskan coal stove and my blower rheostat broke this morning. I opened it up hoping to be able to fix the part instead of buying a whole new fan controller. Any motor controllers that I ...
1
vote
1answer
144 views

Best Way to Heat a Tri Level Home

I have a tri-level home, which is approximately 1600 sq.ft. Presently I have electric baseboard heat, with a pellet stove on the main level. I am looking to upgrade to a better, more centralized ...
0
votes
1answer
24 views

Is ice on ERV door normal?

My ERV is forming ice and condensation on the top of the door and on top of the unit (presumably because the fresh air intake is on that side). The outside tempersture hit about 1 degree F today. ...
1
vote
2answers
809 views

Connecting condensate pump to sewer

My AC condensate pump currently pumps through a vinyl tube directly outside my house. However, I just replaced my broken home humidifier and realized that the previous one never had its drain properly ...
4
votes
5answers
180 views

How to Lower the Ouptut of Oversized Furnace

Questions I would like to lower the output capacity of my furnace if possible. How can I do this? Is it worth doing, or should I just live with it? Is there an easy way? Some ideas: replace burner ...
0
votes
0answers
41 views

How to remove ice buildup from window air conditioner

My fan froze on my AC unit in my bedroom window. I was able to move the inside one when it froze, but this one is on the outside. Should I spray hot water on it to get it to move? I was going to use a ...
0
votes
1answer
52 views

Pilot lights, but main burners don't on furnace with no flame sensor

I have a Rheem furnace in my house. It recently stopped working. It is the type where the pilot is not always on. Anyways, the ignition will kick in, and the pilot lights just fine. However, the ...
2
votes
2answers
65 views

Cost of adjusting the thermostat

Is it more cost effective to (1) play with the thermostat by lowering it at times that you're not home or needing the heat and raising it back later or (2) leaving the temperature on a set amount and ...
1
vote
1answer
40 views

Do all HVAC units have a drain line?

I have a rental unit and I can not find a condensation drain line on the home heating unit. The unit is old and my question is do all heating units have a condensation drain? Thank you
0
votes
0answers
78 views

Why would my heat pump AUX be kicking on with 1 degree change?

So this is weird, and I literally just noticed it today. I have a Honeywell 5-1-1 Day Programmable Thermostat – RTH6450D. That works fine, I have a heat pump system (Carrier 2-ton). Today for some ...
0
votes
3answers
641 views

What is the correct way to seal/flash coolant lines through T1-11 siding?

Our contractor installed an AC compressor and did a poor job of it. He ran the AC coolant lines through the middle of the wall and then just squirted some expanding foam into the hole, like so: (...
1
vote
1answer
92 views

HVAC Contractor Didn't Install Drip Pan

I recently got the A/C unit and furnace in my basement replaced. When the company came out to do the quote, they stated that they thought I should have a drip pan, and the proposal that they gave me ...
0
votes
3answers
90 views

Bedroom not getting enough heat

I have a dedicated HVAC unit for the rooms on the second floor of my house. A bedroom at the opposite side to where the HVAC unit sits doesn't get enough AC or heat. Right now, in winter, that room ...
0
votes
0answers
63 views

Can a furnace safety limit switch with manual reset be changed out with an auto reset switch?

I have a Ruud natural gas furnace from 1987. Overall it works well. I've had my home warranty service send out an HVAC tech a couple times for the high limit switch needing to be reset. It's a manual ...
1
vote
1answer
92 views

It sounds like water dripping when heat runs [closed]

We have a humidifier and I have shut that off but still hear the sound when the heat runs...anybody know any other possible solutions It's is a carrier weather maker 8000vs energy efficient gas ...
0
votes
1answer
323 views

Add a c-wire to 25+ year old Rheem furnace

I've looked at just about every post on adding a C-wire to power a WiFi thermostat but remain uncertain on how to proceed. The current installation on a Rheem RGAC-080A is two wire as here: XFMR - ...