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22

They do exist. Best bet is probably to contact a local sheet metal shop, if they don't have one they can build one. Expect this to cost in the tens of dollars range. You could potentially cap the end, and then use a round duct takeoff. The downside is it will restrict flow to the vent because of the abrupt end and sharp angles internally. There's another ...


16

I assume you are in a cold climate, like Minnesota (where I am). I will address your question in three parts; the first two have to do with the humidifier. The "winter" setting on the duct in your photo: It appears from the photo that the duct in question goes from your humidifier around to the return (intake) side of your furnace's ducting. This needs ...


14

First, what you do not want to use is duct tape, the adhesive fails under the extreme temperatures. For dryer vents and HVAC ducts, you should seal seams with a foil backed tape. This is designed to be airtight and handle the temperature swings that would cause other types of tape to fail. Note: sample product image, no affiliation or recommendation for ...


13

It’s some form of the DSC surface siren. It may have a built in siren driver or it may be “speaker only”. They are typically used with home alarm systems. These have been private labeled over time by various national alarm companies. They are not rated for use in a return air duct, nor allowed by any code. Unfortunately there are many in ducts just ...


12

This will completely depend on the number of elbows, the size of the room being ventilated, and the power of the fan. In general for a bathroom, you'll be looking to have an Air Change per Hour (ACH) of 8. To accomplish this, you'll have to select a fan based on the size of the bathroom, and the equivalent duct length. Bath room size The first thing you'...


11

I live in Florida too so I know exactly what you mean about hot attics. I had the same problem except for the pvc water pipes. I put up a number of 2 by 8 feet of 3/4 inch plywood on the rafters. Where it was possible to move over some of the cables, I did it. where I couldn't move them, I took some 2x4's, notched them for the wires to go thru and put them ...


10

You need a duct crimper like this to reduce the diameter of the end of one piece of duct: Run the tool around the end of the duct so that you have multiple parallel crimps. That piece should slide right into the uncrimped piece, giving you a secure connection to tape. If you don't want to spring for a dedicated tool, I've seen where people use needle-nosed ...


9

For the ducts, the setting indicates where you should set the switch based on the season. If your house has separate air return ducts on different floors or even multiple ducts on the same floor, changing the setting changes which ducts pull air from the house, allowing lower ducts to suck cold air out in the winter and higher ducts to suck hot air out in ...


9

sometimes ductwork under pressure and heat can experience a sudden deformation commonly referred to as oilcanning. this is where large rectangular pieces of box ducts have stiffening ribs formed into them to prevent deflection under pressure. if a particular panel is installed in just the right (or wrong) way, it can temporarily flex when it warms up. its ...


8

There more restricted the airflow is, the more noise there will be. All contributing factors to noise: Diameter of duct (larger is better) Overall length (shorter is better) Number of turns/bends (fewer is better) Radius of turns (larger is better) Size reducers used (no reducers is better) Type of duct (smooth, rigid is better than flexible) Type of ...


7

For the duct work, since we don't know how many cables you are talking about, I suggest ENT (Electrical Non-Metallic Tubing). It is flexible, corrugated and comes in a range of sizes, same as PVC. You can even use PVC connectors on ENT if in a bind. For termination, you can either use a box / terminating structured media center or make your own with a J-...


7

Do the joints in adjustable duct elbows need to be taped as well once they're adjusted Yes, they do. or are they considered air-tight? No, they are not. Far from it, in fact. You want to tape every seam in your ductwork, using (as Shirlock pointed out) foil tape. Each exposed seam, whether it's at a connection or part of pre-formed metal like the ...


7

Yes, that's considered safe. The operating temperature of a dryer vent is not a problem for direct wood contact. Keep the vent clear and you'll have no fire. Ensure all joints are foil taped, so lint does not escape from the pipe. Should lint escape the pipe, it can build up in the wall. Use a "long sweep" elbow to make the vent easier to clean out. ...


7

I'm dealing with the same problem in our "new" (1992 vintage) home. Long duct runs expand and contract with conditioning cycles. In places where the duct is held tightly against the home's framing or other objects, sudden slipping results in pops or squeaks. Solutions generally involve either 1) securing the duct more effectively at the contact point so it ...


7

Most forced-air HVAC systems in Residential are both heating and cooling. What might be efficient in the summer will not be efficient in the winter. So, where do you live and which do you use more? If you live in Arizona you optimize for cooling but if you live in Minnesota you optimize for heating. Then you just deal with a less efficient system in the ...


6

Leather gloves and safety glasses. Wide rubber band wrapped around the duct at the position you want to cut (a wide band stays in position better than a narrow one). Leave a little extra to allow for smoothing out any irregularities at the end. Permanent marker to mark the line you'll be cutting along. Hacksaw to start the cut. With the line marked, it's ...


6

There's stick-on wire chases that can be purchased. I think the usual big box hardware stores carry them. Slide the wire inside, peel off the sticky, and bury it in a corner. You won't see it. Google plastic raceway cable organizers. The first one that came up says it was available in black or ivory. http://cableorganizer.com/economical-latching-...


6

If it is a manual damper, there is usually a wing nut that attaches the handle to the shaft of the damper. If this wing nut is loose, it might allow the handle to turn without actually turning the internal damper. I would verify that the nut us tight and when you turn the handle, you can actually see the shaft rotating at the same time. If the tube of the ...


6

Yes, now a days screws and a sealant of some sort are required. Use aluminum tape, not the gray plastic crap with cloth backing, it falls apart in a few years. There are brush on sealants also.


6

I'm confused/surprised by the existence of the void, but if you've got the space, then go for it. The only bit of mathematics to be concerned with is matching the cross section of the various sections of pipe.


6

24-gauge is 24-gauge. However, the the silver type round pipe is coated with a rather inexpensive galvanizing coating. This coating is to inhibit rust. The galvanizing keeps oxygen and moisture away from the raw metal.These elements will discolor the metal, causing the metal to oxidize and rust, thus shortening the life of the metal. Now for the down side ...


6

Why do you need a duct? Most bathroom vanities, for example, are wide open from a slot in the floor to the louver on the kick panel. Just close off the compartment by any convenient means and call it a day. Staple some cardboard in if that works. And parts from a big box store should work just fine. A common 2x10 or whatever size duct could be laid right in ...


5

Well first, the outlet being at-grade is a no-no for those pest reasons. They don't have to get up the vertical pipe to cause problems; a mouse or bird can nest in there and cause problems. They did it anyway because it was easier to run it down through the crawl space then up to the ceiling (where, if this is your garage, they'd then have to build a sealed ...


5

Don't use duck/duct tape on HVAC ducts, use foil tape. Duct tape isn't designed to take the heat variations in duct work and will lose it's adhesion over time. More than likely you can unscrew this section of duct work and remove it instead of cutting holes. With it removed, you can either fix the damper or replace the section with a new damper. If the ...


5

There are thousands of species of mold known to Science, with different species being found in different parts of the world. There isn't any one "crawlspace" mold or "air duct" mold, it's just whatever spores of whatever species happened to take a foothold there. Which one is more dangerous will depend on the particular species of mold and the sensitivity ...


5

A note on tin snips, which I suggest for this task: if you have a hard time cutting a straight line, make sure you have the proper style. An offset handle helps keep the material from digging into your knuckles. Look for one that is angled up and possibly to the side. Long cut versions (with longer cutting blades) are good for smooth straight cuts in things ...


5

Dryer vents should be sealed with foil tape as they can withstand the high temperatures encountered during machine use. Other tapes, even duct tape, are susceptible to failure under the extreme heat. Non-foil tape can also catch on fire.


5

furnace and hot water heater are a few feet away Combustion air intake which is necessary on an insulated and sealed buiding. Otherwise negative pressure prevents combustion gasses from going up the stack. In the case of any carbon monoxide content, this condition can be deadly. Partition the furnace and water heater off so they're not part of the ...


5

You'd just cap the square duct and install a takeoff in the cap. It may be difficult to find a hemmed end cap in 6x6, but as you can imagine it would be trivial to fabricate a simple wraparound cap.


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