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3answers
50 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 ...
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3answers
20 views

Mount horizontal 6" metal exhaust pipe to wall economically?

I'm trying to add more ventilation to the back room of my garage. The only available outside air exit location is 25' horizontally along the front room of the garage's wall. I have 6" 30ga sheet ...
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1answer
213 views

Why would only 1/3 of my registers be blowing warm air?

I have a Coleman gas furnace in a wall space in my house which somehow shares the blower on my a/c unit on the roof because it turns on when furnace is called to start, though it does bump up after a ...
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2answers
42 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 ...
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1answer
25 views

What is 3" (750Pa) wg class?

According to Sheet Metal & Air Conditioning Contractors’ National Association (SMACNA) - leakage test manual, It is not recommended that duct system constructed to 3" (750Pa) wg class or lower be ...
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2answers
426 views

How to fill / seal in-slab hvac ductwork?

My house is built on a slab. Within the slab are "channels" which act as ducts for the HVAC system. I assume it is partially lined with metal but based on photos from an HVAC-cleaner, it's hard to ...
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3answers
72 views

Duct Cleaning: Is Duct Sealer Necessary, Non-Toxic?

A professional contractor is cleaning AC Ducts, and after he scrubs the ducts, he wants to apply an acrylic duct sealer and de-odorizer. The container of the duct sealer has minimal lableing and does ...
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1answer
63 views

Attic Insulation

I have Insulated AC flex duct work in my attic. Am I correct in that since its insulated already if I lay insulation over the duct work it is fine as long as the duct work is sealed properly? I have ...
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1answer
2k views

Insulating ducts in a crawlspace

Consider a source duct from the furnace/AC. The ducts run in a vented crawlspace. The floors atop the crawlspace are a mix of hardwood and kitchen vinyl. The symptoms are: the longer run vents ...
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3answers
43 views

Sealing gas duct vents with silicone

Is it okay to use silicone to seal gas furnace heater supply ducts? If so, do you know how long the silicone will need to cure before the system is useable? Some background: I've been trawling around ...
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1answer
4k 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 ...
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1answer
26 views

Metal around wall register boot for trim

Below are two images of what im talking about. Around the duct boot for the wall register is a metal box to make up for the difference between the wall and where the trim ends. What is it called and ...
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2answers
5k views

How do I install a jump duct?

Our master bedroom is considerably warmer than the living/dining/kitchen area of our house, and we've been setting the thermostat quite lower than we'd like in order for the bedroom to get cool enough ...
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2answers
73 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 ...
2
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0answers
87 views

Can I use flex duct for a range hood exhaust? [duplicate]

I am replacing an old range hood with a hood/microwave/convection oven. The vent from the old hood does not line up with the vent position on the new unit. I know how to remove the old vent and patch ...
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1answer
841 views

Will splitting a duct to extend HVAC to an addition cause problems?

I'm building a 15 x 26 addition off of current family room to use as a music room. The family room has 2 vents(registers) where the family room meets the new room, and because of convenience they ...
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1answer
1k views

Adding vents to duct?

My house has forced air HVAC. When I finished the basement, I used a closed cell foam insulation that worked very well. The basement will get only 8 degrees cooler than the first floor during a time ...
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1answer
69 views

On wall near floor or ceiling for supply ducts in basement

I'm starting to finish my basement and I'm curious if I should put my supply ducts in the ceiling or the exterior wall near the floor. I have the configuration to easily do either. Any thoughts on ...
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0answers
26 views

Heat Pump Extended Distance from House

I am replacing a Gas Pack with a Dual Fuel Heat Pump. I live in Tennessee so the temperatures are generally moderate. The location of the current pad is right next to the house, between my deck and ...
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2answers
114 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 ...
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1answer
22 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
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1answer
24 views

Should I plug unused chimney ports in basement?

My house used to use the basement for gas heat and the water heater that were using these, 3.5" and 5" ports in the chimney stack. The whole chimney is no longer used but I want to keep the option ...
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2answers
42 views

What's the minimum safe distance from the back of a dryer to a wall?

Let's say I have a side-venting dryer. If I don't need to run ductwork behind the dryer, how close can I safely place the dryer to the wall?
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1answer
90 views

90 degree angle in air conditioning ducts, should I avoid them?

I have forced air at my home and air ducts run pretty much straight. However I want to add bathroom in the basement and because of low ceiling hight, the main air conditioning duct has to be re-routed ...
3
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1answer
43 views

Bedrooms aren't being heated as well after new furnace

When my bedroom doors are closed the room is cold. We replaced our furnace about 5-10 years ago and the repair person said we didn't need as big a unit as we had before and every since then it feels ...
2
votes
5answers
31k views

How to make a 6 inch hole through a brick wall for venting

I'd like to vent my range hood out through an exterior brick wall. How would I go about making a 6 inch hole for the vent? I'd guess I'd use a masonry chisel to chip out the mortar and then pull ...
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1answer
41 views

Repairing a rip in my hvac vent

A small section of canvas fabric connects the duct coming out of my furnace to the rest of the house. I noticed that there's quite a large rip in this fabric. Would it be best to use standard foil ...
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votes
2answers
256 views

How to repair buckled duct work inside wall?

Update I think the duct is actually fine. The duct connects to a register that is shared by two rooms. When heating, one room is gets hot, while the other is cool (not too cold). I think the problem ...
1
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2answers
124 views

How to seal HVAC ducts running through old window to addition?

My house has a small addition that was added by the previous owners. They ran the HVAC ducts through an old window and some of the block: The rectangular section in the window should be easy ...
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0answers
48 views

new furnace hurts eardrums

I just got a new furnace in my 800 sq. ft apartment. Single stage 80% efficiency 40K BTU Coleman. It seems much louder than my old one. The burners and the blower. And when I walk past the (single) ...
6
votes
3answers
1k views

How can I stop our duct work “pinging” at night?

I'm in Canada, and our home is a bit older, ~20 years, and the duct work seems to be making a rather loud "pinging" noise at night. I assume this is due to colder weather in general, and the hot air ...
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0answers
28 views

Temporary Remove Flex Duct

I am about to replace a load bearing wall in unfinished basement. There is flexible duct attached to plenum that I need to temporarily move out in order to put the beams in. Do i just need to cut ...
0
votes
2answers
67 views

Replace or wash this furnace filter?

My mom's furnace has ductwork until right next to the furnace, where the return air instead goes into an obsolete electronic air cleaner that is basically as big as the furnace itself. The issue is ...
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0answers
22 views

Is there a “bending rigidity index” of some sort for semi-rigid aluminum ducts?

Some semi-rigid aluminum ducts bend easily and others do not. I want to purchase semi-rigid aluminum ducts online of a specific bending rigidity/stiffness that minimizes sagging but can be easily ...
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1answer
49 views

Does cold galvanizing compound restore the rust protection of a galvanized duct?

The house is a ranch built on slab on grade with a newer furnace in a downflow configuration with A/C. The in-floor clay tile supply lines are in good shape and clean. The original 60 year old ...
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1answer
837 views

How to run duct work for basement dehumidifier?

Our basement is partially finished, approximately 50/50 in terms of square footage. It was used as a mother-in-law suite at some point by a previous owner. The finished rooms are air ...
0
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1answer
95 views

What is this 6" vent coming out of the main furnace trunk going under my deck for?

I have a 6 inch round duct that comes out of the main trunk about 5 feet from the furnace. It runs through the basement and outside the house (under the deck). What is this? The furnace also has 2" ...
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votes
2answers
10k views

Why am I finding condensation in my dryer?

I live in Houston, TX (Very Hot, Very Humid). In the summertime, my dryer is dripping with water, when not in use. I do not have overly excessive drying times. My dryer is vented via an unfortunate ...
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0answers
66 views

Older home with no AC plenum…replace our entire AC system as suggested?

We have an older home that has a large living-area/fireplace room; the AC unit sits over it in the attic. Earlier this year, in that room, we noticed a crack beginning to form in the ceiling sheet ...
3
votes
2answers
4k views

How can I quiet a bathroom exhaust fan that became loud only after the duct was added?

I had a fan added in my bathroom. Surprisingly there wasn't one at all. When the fan was first installed they had it venting into the ceiling. It was a .5 sone fan and you could hardly tell that it ...
0
votes
1answer
73 views

When installing rigid dryer vent and connecting pieces

When installing rigid dryer vent and connecting pieces together do I use foil tape or those circle things you put on outside with a screw to tighten? Also is it a good idea to use duct connectors ...
3
votes
2answers
354 views

Flooded HVAC ducts

I own a house (Built in 1966) on a shallow hillside, around which recent rain has caused complete ground saturation. On my bottom floor, which is on a concrete slab, the three floor vents were ...
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2answers
44 views

Finding air leaks in ducts

I've been sealing the ducts in our basement with mastic. I've done a decent job, but I'm trying to find every leak in the basement, where it's accessible. For instance, I stand on the ladder in one ...
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3answers
2k views

What is the best way to clean a dryer vent?

I posted this questions 6 months ago.. Why does it take my dryer 3 hours to dry a load of clothes? I checked the cycling thermostat and thermal fuse. They are operational. I have seen different ways ...
0
votes
1answer
712 views

Duct static pressure vs ambient air pressure

I've read that air handlers are typically rated for 0.5 iwc. Doing a simple conversion, this comes out to about 125 Pa. Is this with reference to the ambient air pressure? So, if I had an absolute ...
4
votes
6answers
8k views

How do I cut Semi-Rigid Aluminium Ducting?

I wish to cut the duct work without damaging my hands or my wife's kitchen scissors. So what tool should I be using? (Trying to get the ends squared using a freehand hacksaw does not look easy.)
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2answers
144 views

Is having a branch off the end of main heating HVAC duct bad and if so, why?

Question: Is having a branch off the end of main heating HVAC duct bad and if so, why? Background: A heating and cooling contractor sales representative came to my home today. He saw the situation ...
1
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1answer
152 views

What should we do about asbestos tape on heat ducts?

My daughter just had a home inspection of a home from 1900 and there was asbestos tape noted on the seams of the duct work. What should we do? And I am assuming it is not only on the visible ducts. ...
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2answers
21k views

What type of tape do I use on a dryer vent?

I need to install a dryer periscope vent in my new dryer unit, However, it needs to be sealed for leaks. What type of tape should be used to tape a periscope dryer vent?
1
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1answer
1k views

Appropriate register for duct size?

So I asked a long-winded version of this question in another thread, but haven't really received any good responses yet. I'm going to condense and try again... There is an 8" duct feeding a 6x12 ...