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11 views

What cleaners are there in the market to use for Air duct duct cleaning?

My house is near to the mountains so I' am unable to get any help from Air duct cleaning Denver experts as they are unable to come over my house. Can any body suggest me some cleaners used for air ...
3
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1answer
44 views

How can I remove ductwork that is butted against a foundation wall?

I need to remove the existing ductwork in my basement to install insulation behind it. I'd like to do it without destroying the ductwork. The vertical duct is right against the foundation, so I can't ...
0
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1answer
56 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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0answers
15 views

How do you apply the Equal loss friction method when your furnace has extended plenum in two directions?

My furnace has the extended plenum in two directions (one main duct goes to left, the other goes to right) Do I have to calculate one longest path for each of these extended plenums?
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0answers
21 views

How do I measure the size of a duct that runs through a finished wall (the register end is accessible)?

I am trying to redo a Manual D for my house (heating mainly). I can pretty much determine the length of each run but I can't figure out the exact size of the ducts that are already installed The ...
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1answer
56 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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0answers
19 views

Do I need a damper on both ends of the ducts on my kitchen range hood/extractor?

My new kitchen range hood is compatible with both 3-1/4" x 10" rectangular ducting and 7" pipe ducting. It includes a damper for the 3-1/4" x 10" format, and an adapter plate for 7" - no damper was ...
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0answers
26 views

What could be the reason why all my registers at foundation slab level have weak air flow?

In the picture below all the ducts that have a long leg going toward foundation have weak air flow. Read the details on the picture Could anybody tell me what is the problem with these guys? The ...
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2answers
59 views

How do I calculate CFM for a structure?

This is for calculating the CFM (cubic feet per minute) of air that the blower needs to move in order to compensate the total heat loss (ventilation,infiltration,heat loss through walls, windows, ...
0
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2answers
86 views

Can I move second-floor duct-work from the floor to the attic

I have a two story home that sits on a slab. There is some duct work that runs through the slab. I have some duct work that runs through the ceilings of the first-floor and points towards the floor of ...
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1answer
46 views

A professional to test asbestos safety in furnace ducts

We live in a rented house with an old furnace duct system (probably 1960's). There is asbestos-containing duct-wrap all around the ducts, and it starts to crumble in some places (it's located in the ...
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1answer
47 views

How can I build custom air ducts for an in-wall heater?

I have a in-wall heater just like this one: It sucks cold air from lower part of vent, heats inside, and blows it out in the upper part of the vent. Now I have the basic problem of putting a ...
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4answers
98 views

Is it safe to use an HVAC system even though the duct wrap contains asbestos?

In our rental house the furnace ducts are very dirty. We brought an expert to clean it, but he said he just won't do it because the tape around the ducts (in the attic) is probably asbestos. After ...
2
votes
1answer
211 views

Can I cap the air return in my unfinished basement?

I noticed today that there is a massive air return in my unfinished basement. The opening is about 2 meters from the blower, and as large in diameter as the return duct coming from the upstairs. This ...
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0answers
61 views

Can I cut out the sill plate to pass a duct through a load bearing wall?

I need to pass an HVAC duct through a load bearing wall into the basement below it. I can't seem to find a code reference in IRC for what I am allowed to do with respect to notching or cutting away ...
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2answers
53 views

Is it possible to create a better temperature controlling system?

I have a two story 2.5k sq ft house with a varying degree of temperature throughout the house. The main problem is that the air coming out of vents are very weak if almost nil. Only the living room ...
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0answers
32 views

Lint when running AC

There seems to be a lot of lint when I run my AC unit. I have recently replaced the filter and made sure that the filter is put in correctly. What could be the issue?
0
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1answer
74 views

Central Air duct does not blow

We moved into a new house last year, the central A/C works great for all the rooms (even for closet) but we have a problem in just one room. There is almost no air flow coming from that room's air ...
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0answers
137 views

Soundproofing existing ducts/vents in basement (drywall is already up)

So long story short I recently converted a basement into an apartment and plan on living down there. I insulated in between the joists and double drywalled everything and that is all ok. The only ...
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1answer
43 views

Should I add an escape register for added ventilation in A/C duct to reduce condensation?

I have a condensation and drippage problem where my 8" exposed circular AC duct comes out of the ceiling. Above the ceiling is the attic, meaning it gets pretty hot. The pipe comes out of the ceiling ...
0
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0answers
35 views

Asbestos in close proximity of floor repair

I have a floor repair to make in a 1950's home that had the large in floor central heater installed that has long been removed. The owner wants the grate removed and flooring toothed back in, matching ...
4
votes
3answers
785 views

Is there a trick to getting round HVAC duct pieces to fit together

I have been doing some basic HVAC duct work as part of a remodeling project and I can never get the pieces to fit together without massive amounts of elbow grease and mangling the ends. Is there some ...
2
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2answers
80 views

Can I remove the insulation from flex duct

I am trying to fit a 7" flex duct between some floor joists and it would fit better without the insulation. Can I remove the insuluation and just use the plastic part?
0
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1answer
45 views

Would a radiant barrier help stop this heat transfer?

Using my nifty thermal camera, I discovered that my furnace closet's combustion air duct (visible in this question) is getting really hot when the attic heats up, and then (being sheet metal) it ...
2
votes
1answer
283 views

Can I properly install Roxul mineral wool batts in a mostly-drywalled stud bay by pushing them up from below?

Using my nifty thermal camera, I discovered that my furnace closet's combustion air duct (visible in this question) is getting really hot when the attic heats up, and then (being sheet metal) it ...
0
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2answers
546 views

Is 20 feet too long to run bathroom fan duct for 100cfm fan?

I need to run about 20 feet of duct to reach the gable, I don't want to go through the roof unless I absolutely need to, I live in Vermont and we can get a lot of snow build up on the roof, I also ...
2
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2answers
1k views

Should my furnace closet have this huge duct opening into the unconditioned vented attic?

So my interior furnace closet has a huge duct in it that connects the closet to the unconditioned vented attic right above it. Needless to say, this is a huge air leak into the conditioned part of the ...
0
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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 ...
3
votes
2answers
428 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 ...
0
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1answer
968 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 ...
2
votes
3answers
202 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 ...
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1answer
900 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 ...
2
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1answer
1k views

What can I use to adequately insulate round rigid metal ducts?

I'm installing properly sealed round metal ducts in my unconditioned attic for heating and cooling. I've probably got 100' total of 6" duct to cover. I'm trying to achieve an R-8 insulation value, ...
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3answers
2k views

How should I route my dryer exhaust pipe?

My existing dryer vent run enters the crawlspace behind the dryer and exits through a vent that is part of one of the normal crawlspace vents. Since the house sits on a slight slope, the crawlspace on ...
1
vote
3answers
650 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 ...
3
votes
1answer
150 views

What is the purpose of this outside air return in my utility room?

Curious what the purpose of this duct is and whether I can close it off. It goes directly outside. I was planning to convert this room to an office. The furnace and hot water heater are a few feet ...
4
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1answer
8k 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
vote
1answer
236 views

Can I connect two separate ducts systems together?

My apartment, which I own, is split upstairs by two hallways. Each hallway has its own A/C unit, to cool 6 single person rooms each. Recently the south side A/C broke. I have called the repairmen out ...
3
votes
1answer
178 views

Should I use a quick or gradual 90 in my flexible A/C ductwork?

To elaborate a bit more. If you are running an 8" duct off the supply, would you do a quick 90 degree towards the destination or do a gradual 90 degree? I would guess a quick would be better because ...
3
votes
1answer
3k views

Where should I tap in to the existing duct work?

Bought a 1981 repo a year ago. The house measures around 900 SQFT. I enclosed the one car garage (10'x20') @ 200 SQFT to serve as an office. The front of the garage is insulated (10') along with the ...
3
votes
1answer
135 views

Can I install wiring in the space used by a sealed air duct and PVC water supply lines?

I have a space between walls that is about 14" deep and 8 foot wide, and goes from the floor to the ceiling. This space is on the second floor. Petty much in the center of the house. The space ...
0
votes
2answers
546 views

What do I use to cover an insulation wrapped duct? (Silver foil wrap?)

I was looking for silver foil to cover the heating duct insulation wrap. What is it called?
4
votes
2answers
1k views

How do I improve heating in back room of house?

The back room of my house is quite warm in the summer. The room is on the north side of the house (Alabama, USA), so the outside walls don't get direct sun exposure. The attic insulation is a little ...
4
votes
1answer
825 views

How do I lower the humidity in my non-vented laundry room?

I've lived in my house for about a year now and I have this small room (maybe 5x6) that contains my washer and dryer. I have central air and this room does not have a vent. Also this room does not ...
1
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2answers
179 views

Is it safe to install a heating duct register in the ceiling directly above a home entertainment center?

We're in the process of getting bids for central heating and one of the conundrums is where to position the registers. Due to the layout of our living room (and style preferences of my significant ...
10
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2answers
13k views

What does a Summer/Winter switch on furnace air ducts do?

On some of our furnace ducts, there is a switch/valve for Summer/Winter or S/W. What does changing this switch/lever accomplish? Can bad things happen if I forget to switch it? Bonus question: ...
4
votes
1answer
605 views

How can I unbend a bent furnace filter slot?

I recently bought a new home. When going to change the furnace filter, I couldn't get the original furnace filter out of the slot at the last part of the filter (where the cardboard border is). Since ...
3
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2answers
241 views

How can I neatly install temperature probes in my ductwork?

I'm planning to install several temperature sensors in my hot-air furnace's ductwork, specifically in the return duct and in the supply plenum of each of our two furnaces. The sensors I plan to use ...
2
votes
1answer
384 views

How to remedy noisy air ducts?

I have forced air extraction with a duct running through one classroom then a second. The classroom which is ducted closer to the fan receives much greater air flow through its vents. To combat ...
4
votes
2answers
871 views

Do joints in adjustable duct elbows need to be taped?

Do the joints in adjustable duct elbows need to be taped as well once they're adjusted or are they considered air-tight?