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0
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1answer
22 views

Whole house dehumidifier- freestanding vs vented

I’m considering the purchase of a Dehumidifier for our basement, to avoid mustiness in the unfinished/unconditioned portion. I want a nicer quality HVAC-grade unit, both for energy-usage reasons and ...
0
votes
3answers
47 views

What type of crawlspace setup do I have?

New home owner here - I’m working on sealing the furnace ducts that run through our crawlspace. Previous owner used silver duct tape and not the proper mastic or UL approves aluminum tape. Long story ...
1
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2answers
30 views

Is a gravity or spring damper sufficient for a make up air vent?

I am planning on installing a make up air vent in my cold air return. I don't want to install an electric system that I have to wire to 3-4 different appliances. Is a gravity or spring loaded damper ...
0
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1answer
30 views

Will a make up air vent cause an issue in the winter?

I recently installed a gas range and I will soon be installing a 300cfm range hood. Since I primarily burn wood in the winter for heat and I don't want any back-drafting issues, I am planning on ...
2
votes
2answers
48 views

Is there any reason that plumbing can't be adjacent to a heating/cooling duct?

I'm installing a utility sink and the only place to put the plumbing (if it's going to be right under the sink) is either directly behind or infront of this vent... Is there any reason not to put it ...
0
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0answers
14 views

Exposed spiral duct clearance

I'm replacing concealed (in a furdown) rectangular HVAC duct in my kitchen with exposed spiral duct. With an eye toward maximizing head room (ceiling height is 9 ft), I would like to mount the spiral ...
0
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0answers
28 views

Round metal duct leaking water at crimped joint

Noticed a water leak stain in my ceiling in the drywall. Cut a hole and noticed water drops dripping from the joint of a metal round air duct. This duct leads to an external air vent on the side of my ...
1
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0answers
31 views

How do I calculate fan size for a single room exhaust system to reach a desired cfm when restricted to specific duct size/route?

I am wanting to exhaust a sealed room (except for air intake and exhaust). The room is 512 ft3, and due to positioning, orientation, and existing construction, I am restricted to using 6" flexible ...
11
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2answers
3k views

What is this device I found in my HVAC duct?

I was looking through my HVAC ducts with a camera and found this device attached to the side of a floor joist. It is about 2-3 feet from the air return vent. What is it?
3
votes
1answer
94 views

How can I reduce noise from tenants coming through my heating duct?

I live in an old house with a wood frame and forced air heating. My family lives upstairs and we rent out the bottom floor. My problem is that the sound from my tenant's bedroom travels directly into ...
1
vote
2answers
65 views

Is there some type of coating I can use to prevent condensate on my HVAC ducts?

I'm getting a lot of condensate on my HVAC ducts that run though my first floor (and HVAC blower) especially in July / August when humidity levels are outrageous (in NJ). The 1st floor space space is ...
0
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1answer
27 views

6" Ducting straight to in-wall rectangular ducting

I have a vent for the microwave-range that goes from an interior kitchen wall to the outside of the house. I need to re-locate this, but I can't move the exterior vent fixture. It currently comes in ...
3
votes
0answers
37 views

HVAC: can a motorized damper be installed inside existing ductwork?

My HVAC system consists of a fan, furnace, compressor-driven AC, and evaporative cooler. The problem is that there is a large air volume used only by the evaporative cooler that is generating a lot of ...
1
vote
1answer
81 views

Is my plan for moving return duct a few inches ok?

Below is my ac unit and the return duct that connects to the blower. I currently slide my 1-inch filter under that pvc pipe that's inside the furnace. PVC is in the way and there is no L-shape latch ...
0
votes
1answer
42 views

How to Sync Booster Fan with Furnace Fan

I own an old house. Some of the rooms in the house that are too far away from the furnace are not getting enough air, the airflow is too weak. I tried to close as many of the other ones as possible, ...
0
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0answers
24 views

Hood vent duct in floor - sealing it

I have an 8" duct that comes up through the kitchen floor (runs in subfloor between basement and 1st floor and vents outside) and through a kitchen cabinet bottom that will house a pop up vent. I can'...
0
votes
1answer
244 views

Should vent directly above furnace be open or closed

There is a vent in the duct directly above my furnace. This is in the air out side, not the return duct. Is there a reason I should have this duct open? It was open when I bought the house a few ...
0
votes
2answers
442 views

Sloped ceiling - remove hot air with exhaust fan

I have what I think is an unusual setup of a sloped ceiling that may offer an easy fix to my problem, but wanted to get some opinions from you guys. Our master bedroom, on the 2nd floor (top floor), ...
1
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1answer
36 views

Is there a way to change the location of HVAC air filter location?

We bought the house recently. Heating system was recently installed by the previous home owner. I cannot believe they did not think of this but the place for filter is inside the furnace. The problem ...
0
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0answers
21 views

Is it normal for metal ring clamps to not make duct work air tight?

I connected some 4" round ducts recently that vented to the exterior. As I looked at them, I noticed, I could see light. I've shoved these ducts in as deep as I can get them (that's what she said) ...
2
votes
1answer
79 views

Is it safe to use a flexible duct near the end of an 18ft dryer exhaust run?

I'm replacing a gas dryer in a condo that previously had 2 plastic flex pipes and a 5ft aluminum rigid duct. I planned to replace it with rigid steel. I got most of it dry-fitted correctly, except ...
3
votes
1answer
97 views

What purpose does the lining inside sheet metal duct serve?

Sheet metal ductwork is often lined inside with a black fiberglass insulation material. What purpose does the lining serve? Insulation is one answer, but ducts can be insulated on the external ...
5
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0answers
55 views

Do I need a wall thimble for thermal separation with a category III venting appliance?

I bought a tankless water heater that allows me to vent using category III. I've seen that wall thimbles are included in many category III termination kits, but am wondering if they are really ...
0
votes
1answer
118 views

How do I patch a subfloor over a return duct cavity

I need to patch these holes in the subfloor where the vents are. These holes are from a return vent that is being moved, the joist cavity below these holes is a return duct. I'm assuming using ...
0
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0answers
18 views

How to fix noise in my bedroom since change of furance/ac but not air ducts?

I had furnace company back out and he told me it is probably a problem with a damper but it would be hard to find out where. It is only loud in my room on second floor but not in other bedroom next ...
1
vote
1answer
66 views

Is it safe for dryer vent ducts to overlap in different directions?

Hard to describe this in the title. What I'm referring to is how segments of duct overlap each other where they are connected. Ideally, as with plumbing, the tube the flow enters should be overlapped ...
1
vote
4answers
62 views

Can I convert galvanized ducts to wood stove black ducts by coating it with high temp RustOleum paint?

I compared the black ducting for wood stoves with regular galvanized ducting and found that they are both 24 gauge and I noticed they are both steel since both tug magnets. There is quite a large ...
0
votes
1answer
38 views

Placed Fire Place Insert Wood Stove into Fire Place; how to minimize heat loss through former chimney damper opening?

The chimney damper for our fireplace is the standard dimensions of 24" x 5.5". I removed the metal damper when I bought the fire place insert wood stove so there is just the damper opening with said ...
1
vote
2answers
318 views

Can I install a modern furnace without ductwork?

I removed an old coal furnace from my basement. The furnace did not have any duct work to speak of. There was an exhaust pipe which fed into the chimney and a duct that went into the next room, but ...
2
votes
1answer
295 views

Why is there a vent on the ductwork coming right from the furnace?

Why is there a vent on the ductwork coming right from the furnace? I have a typical furnace for a 1400sqft house in Michigan. I also have central air which runs through the same duct work. There is a ...
0
votes
0answers
45 views

Can I put a fresh air intake near from a kitchen range vent

I have a question regarding the code for fresh air intakes. I saw in the code that a fresh air intake must be at least 10 feet (or 12, can't remember) from a 'contaminated' air exhaust. I assume ...
1
vote
2answers
2k views

How long can I run a vent duct for a new bathroom exhaust on an old house that doesn't vent out properly?

all. I live in an old Edwardian home where the attic above is a finished loft space so I can't run any ducts upward. I have a second floor bathroom below that needs to be vented correctly. Right now ...
0
votes
1answer
396 views

Need Assistance Wiring a Duct Booster Fan

Morning, folks. And thanks in advance for any assistance you can provide. We have an in-line duct fan in the attic. It assists in moving air from the central HVAC system into our addition. It is ...
0
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0answers
27 views

Debris on duct work

I have drop ceilings in my basement, but was up there to do some work recently. I noticed some debris on the air ducts. I was wondering if anyone knows what it is and whether or not I need to be ...
1
vote
3answers
286 views

Can I funnel the output of a portable air conditioner to direct it?

I have a portable air conditioner similar to the one in the picture below. I want to direct the output flow through a small duct system to the feet of people sitting on a large table. Can I just tape ...
0
votes
1answer
229 views

Fiberglass or reflective roll insulation for duct work?

I have some exposed duct work in my garage. I am looking to insulate it and was looking at the types of insulation. Is is better to use fiberglass or "bubble wrap" reflective roll insulation? I live ...
0
votes
0answers
29 views

8 in thimble, 6 in pipe

I just installed a wood stove in the addition I built for my trailer. My father-in-law insisted on going and buying me an 8 inch thimble for my stove pipe to run through the wall. My stove pipe is ...
1
vote
2answers
703 views

Replace Over the range microwave with hood

I currently have a ductless over the range microwave. It's too close to the range. The heat from the range is melting the microwave handle. I want to remove the microwave and cabinet and replace it ...
1
vote
1answer
504 views

Dryer venting options on second floor with gambrel roof

In redoing our second floor laundry closet, we'd like to replace the flammable flexible plastic dryer duct with rigid duct and a better vent. I did extensive research, but couldn't find any ...
2
votes
1answer
174 views

Can I replace round ducts with rectangular ducts in a basement renovation?

I'm renovating my basement and the big round 7" ducts that cross under the ceiling joists are in the way. I'd like to convert them to 3.25" by 12" flat rectangular ducts, so that the ceiling can be ...
0
votes
0answers
69 views

how to deal with oversized furnace

I recently got a new furnace for our 1200 sqft house in Denver CO. We are planning on adding a second story in a year and I was going to wait until we did that to replace the furnace. Then the furnace ...
0
votes
1answer
344 views

How best to secure rigid duct near a ceiling penetration

In order to vent a kitchen cooktop exhaust hood I am running rigid 6" round metal duct from my ceiling to a roof vent. The cooktop is on the front wall of my house. For aesthetic reasons I wish to ...
0
votes
0answers
269 views

Increasing exhaust fan duct size

I have a bathroom exhaust fan that has a 3 inch duct outlet. However, I would like to use a 4 inch insulated flexible duct. Is there an adapter I can use to accomplish this or do I have to first use ...
0
votes
1answer
71 views

Are these AC ducts beyond cleaning?

I moved into a upstairs apartment- studio 425 sq feet. The building is a 2 story building. It was built in 1971. I had a bad musky meldew smell in my apartment. My AC broke and the landlord placed a ...
4
votes
1answer
611 views

Dryer Venting Woes - what to do?

I can certainly collect some pictures for this but I'm hoping on sound engineering & design principles I'll get a recommendation worthy of executing to that meets code. I have a vented clothes ...
1
vote
3answers
144 views

How to cool a server closet with window?

I put 2 servers in my closet which run at about 90F. The closet has a window, but simply opening the window doesn't drop the temperature very much even when it is 60F outside. If I open the closet ...
0
votes
1answer
412 views

Ducts Spray Foam vs. Wrapping [closed]

I'm having some condensation issues with ducts in my basement. Based on what I've read, it sounds like I have to get a dehumidifier and wrap the ducts. I've wrapped a few, but it's hard to get the ...
1
vote
4answers
119 views

How should I fasten air exchanger ducts to unit?

I have an air-exchanger, and the hoses are little loose. That is I can feel the air flowing out between the motor and the hose. Here is a picture of the overall thing: Here is closer picture that ...
1
vote
1answer
79 views

Can a portable swamp cooler be hooked into a central air duct and recirculate?

I know that normally, swamp coolers take in external hot dry air, and put it out as cool wet air. I live in the hot So. Cal. desert area. A small swamp cooler is cheap to buy, but won't do my whole ...
3
votes
2answers
139 views

What is the proper way to connect a 4“ dryer exhaust to a 6” PVC wall exhaust?

Our dryer exhausts through a 4" opening, but the wall exhaust we will connect to is 6". The previous owners left an elbow / reducer, but it's beat up and basically falls out of the 6" PVC exhaust. ...