9

Sometimes ductwork under pressure and heat can experience a sudden deformation commonly referred to as oil-canning. 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. It'...


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 ...


8

The best way to eliminate transformer noise is to purchase a quality transformer. The noise is because the laminated core is heavily loaded or overloaded and the plates are actually vibrating because of eddy currents. I can’t quite make out the size, but it looks like 24V, 20VA. I would bump it up to a 24V, 40VA unit that would be compatible with video ...


7

Standard EMT tool for tempered glass car windows (after taping - packing tape preferred over duct tape) is an automatic center punch. A hammer and nail will work the same, it's mostly being a one-handed tool that's easy to carry that makes the ACP the preferred tool among EMTs. If you're "smashing the whatever" out of it, you're doing it wrong. It just ...


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 one or more of the following: securing the duct more ...


5

Stick a sponge at the bottom the drips will land quietly on it and when it pours the water still flows through.


5

I don't think the problem you're having would be solved by a fan delay. When the fan turns on, it has to purge all the "cold" air from the ducts, before the warm air reaches the registers. There's not much that can be done to solve that problem, other than having really short duct runs. If you did add a delay, the system would likely overheat. This could ...


5

If you only have access to the inside of the duct, and then only as far as you can reach, you won't be able to make a huge difference, but you might be able to reduce it a little. The sound is transmitted in mainly two ways, some is conducted through the metal of the duct and some is reflected around the inside of the duct until it reaches you. You can ...


5

First, even though the exposed wires are low-voltage, likely 16 VAC, they should be covered for esthetics (if the transformer were accessible to children, not inside a closet, it is likely required). That said, the buzzing noise is likely being transmitted to the metal plate and wall, which make it much louder. A few things to reduce the buzz: Remove the ...


4

Forget any suggestions for restricting the airflow at the grille. The proper way to control airflow in ductwork is with an in-line damper which is placed as far up line as possible in the trunk or branch without affecting any duct drops that don't need the airflow restricted. The reason for this is efficiency and noise. I'm writing this from my phone, but ...


4

That noise can really get annoying. Hate to say it, but I'm not sure there is much you can do about it in your house. However, there are steps the utility company can take to mitigate it. Here is a writeup of what you are dealing with: https://electrical-engineering-portal.com/transformer-irritating-hum They may have to adjust how it is mounted, or ...


4

A "globe valve" would be more suitable for the task. Both ball valves and gate valves are intended primarily for shutoff - either fully open, or fully closed. A likely noise source is cavitation (bubbles forming and then collapsing) at the sharp edges in the flow when partially open. A gate valve has a plate with a (relatively) sharp edge that will ...


3

This is the sound of metal pipes and radiator components expanding and contracting. As they do so, they rub against other fixed parts, like wood framing, brackets, etc. If they stick slightly, you'll hear a popping or clicking sound as they stick and unstick from the friction against this expansion and contraction. So the solution is to locate any points ...


3

One of the adjustment screws is for the swing speed, and one is for the latch speed. It sounds like the latch speed is too high. Adjust the latch speed until the door is just moving fast enough that it closes. You'll also want to be sure to test it by opening the door the minimum amount someone would open it. If it doesn't shut if you slow it down at all, ...


3

There are soundproofing curtains and soundproofing panels that can be found through an internet search for soundproofing curtains. They are not cheap, window curtains starting in the $300 range for an average size window (and yours are much larger). Panels start at about $200 for a 4x8 foot unit and they still need to be hung on some sort of frame. ...


3

Completely noiseless is a high goal - it can be done, but may increase the expense considerably. Quieter than a badly designed hot air system is much easier. In-floor radiant heat, embedded in concrete or gypsum cement, offers essentially silent heat delivery (so long as the pumps are properly sized) - the boiler or hot water heater providing the heat may ...


3

There are all kinds of special sounds absorbers for ducts. They are not the lightweight acoustic egg crate shaped foam, but very heavy and somewhat flexible, but not springy. They lower the Q Factor of the sheet metal. McMaster sells them: http://www.mcmaster.com/#sound-control-duct-silencers/=zyyku7 The same page also has sound control coatings that work ...


3

I don't think cleaning the coils is going to solve the clicking noise, that is probably a more involved repair. Since the coils are not in the compressor compartment shown in your photos (which would have been my first guess), the coils may be literally on the bottom of the refrigerator, usually accessible from the front panel at the bottom of the fridge. ...


3

Cut out the 1/2" drywall in the affected area & hot-patch in 1/4" drywall. A gap won't wear out over time, but any & all padding, greasing or spraying will. But yes, even a slight temperature increase will expand plastic plumbing.


3

Sounds like a broken or worn-out "vibration damping mount.the inertia of the internal moving parts at shutdown will cause the hole compressor to rotate up off of the mounting and slam back as gravity and the rubber nounts return it to its normal position. Common caus of the noise you describe. Fix find a similar mount to replace the broken one. At a used ...


3

Why not just put up sound barrier screens around the noisy desks. To make this work you will have to, as a minimum, keep it to one person per desk and where desks are adjacent move them apart enough to allow the barrier screens to stand in between the desks. Here are a couple of possible examples:


3

Many fan coils do have a delay for the fan. A solid state delay and relay could also be added to a fan coil unit. However the air is not actually cold but room temperature except for any air trapped in the ducts which needs to be purged anyway so a delay wouldn’t help. Any little heat being produced by the heat pump will go into the house so the only thing ...


2

The outdoor units are meant to have water hit them. Only a flood or major major standing water would hurt the unit - unless the water came down at such a high rate that it bent something. Go outside and look at your unit. It will have a "section" or box with the electrical compontnents. It would basically have to flood to that height to hurt your unit. ...


2

There are special screws for squeaky wood floors. You drill a small pilot hole, drive in the special screw and the head of it breaks off. The screw pulls the offending pieces together eliminating the squeak. You will want to try to screw into the stringers for the best result. With the head broken off a small hole remains that can be filled. If you have ...


2

Before you tear up the floors, which is messy and expensive, how bout getting an area rug (they can be cheap at Target, etc.)? If the area rug works, then you know the problem. My concern is that the frame of the building is such that the noise is not related to the type of floor material. The sound may be transferred through the joists and walls.


2

Every 3db is double the power of the signal (amplitude), however this is also the point at which most humans report hearing a noticeable difference. Most humans will perceive the volume to double around 9-10dB. So if you found one door that offered 30dB of noise isolation, and another that offered 40dB, you would say that the 40dB is "twice as quiet as the ...


2

Really really difficult. I had a house that I tried to insulate the noise from upstairs. I put on the upstairs floor two layers of 1/2 inch drywall covered with 3/4 inch ply (with no fasteners) and then carpet on top. It made perhaps 25 percent difference. If you were to hang extra layers of drywall on the ceiling, you would have to fasten it with screws ...


2

Read about bass traps. There are all different types; you can build your own or buy one pre-made. It sounds like for your situation, a correctly tuned Helmholtz resonator will accomplish the task in a small package. It's supposed to be cheap and easy; try this calculator. You can determine the frequency of your noise with this app or similar. Make sure ...


2

Do NOT attempt to make any modification to a common hallway door without at least consulting your local fire marshal. It is very likely that is it legally required to be fire rated, and your modifications very likely invalidate that rating. If there is a fire in your building, and investigation reveals that you modified your door, you could be held liable ...


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