I’m working on a project that involves pumping water for several hours a day from a storage tank to a solar heating collector.
Water is piped from the tank through the pump and into the collector above it. The whole setup is outdoors.
The problem is that the pump is incredibly noisy whenever it’s active. How do people usually go about silencing or at least decreasing the volume of these things? Budget is a concern, so if there are any cheap/DIY methods of doing this, even better.
Here’s a picture of the pump – it’s all wrapped in heat insulation, but the part with the black wrapped wires going in is the actual pump. Part of the problem is that the entire pipe above the pump vibrates along with the pump and amplifies the sound.
I’ve tried wrapping it in layers of fiberglass insulation, but that didn’t do much. Would sound/acoustic foam work better? How would I go about wrapping it around an irregular shape like this?
And if something passive won’t work, would it be possible to record the pump’s whine, invert the waveform, and continually play it back as a form of active noise cancellation? I imagine you’d have to sync up the waves rather precisely to cancel them out, which can’t be an easy thing to do… or is it?
Since it’s a closed system and not potable water, I believe you should be able to add a water pump lubricant to the tank that would quiet the motor if the noise is from the bearing and seal portion of the motor. An automotive type should work. I would Google solar systems for this because it must be common.
do not wrap the pump with anything, it needs air to cool or you will burn it out.
get all the air out of the system that is one of the biggest noise producers.
you foam looks to be very dense like high temperature type. is it? low temp foam will melt. you could use 45 angle cuts at corners for better coverage of the pipes.
if you still have noise after getting the air out then you could place a stereo nearby and play your tunes loud. you could also make a larger box out of some material (rigid foam would be light weight) and line with polyurethane foam, if spiked or irregular surface the better) and place this over the top, you would need U shaped cut outs to fit over pipes so this would be a sound baffle box.
I’m sorry I wasn’t clear. It’s not a closed system and it IS potable water – it heats tap water from the city and outputs hot water for a sink.
I did try a Google search (many, in fact) but could not find anything that seemed like it would work. Most were for RV and sump pumps that suggested basically insulating it with foam, which is what I tried (perhaps poorly) and/or getting a quieter pump (which isn’t an option, unfortunately).
How is “wrapping” different from surrounding it with a baffle box?
Is this possible in an open system? It takes in tap water, runs it through the solar collector, and then stores it in a the water tank until a sink is turned on. Meanwhile, the tank itself has an open access hole (in case of overflow, perhaps?)
The system was set up by a third party, and I’m afraid I’m not sure what type of foam it is… how would I tell?
As for the cuts, even the straight pipe sections vibrate like mad, so I’m not sure that covering the corners better would help much… or would it?
If I’m understanding you right, you mean I’d fit an enclosed box over the whole pump, but instead of FILLING it with foam, only LINE the inside surface of the box and then leave some airspace between the foam and the pump…?
Year-round, actually. Here’s another picture. It’s for a small local farm which has no electricity aside from a few PV panels and no gas, so this is how they get all their hot water. Full details here, if you’re interested (beware: long).
wrapping the motor is an insulating jacket which keeps heat in. the sound baffle box would be much larger than the pump and would have air space for the pump to loose heat into. yes the larger box is just lined with foam.
the foam would have been labeled where sold as high temperature foam. if it’s been used in summer and not melted to the pipes it is likely high temperature foam. the angle cuts would just be better thermal insulation.
a closed system is more likely to have air bubble problems.
So to follow up with your idea, I’m thinking of ordering six of these soundproofing panels and gluing/taping them to the inside of a box made of lightweight wood or recycled plastic containers. Do you think that would work?
if things vibrate then a cure is to provide support. you might make a grid of supports to the tank supports and collector supports. you might try larger pipe support clamps that will fit over and compress the foam yet to allow some movement to accommodate thermal expansion (so not the size for the bare pipe but what would fit over squished down foam).
Wrapping it will not eliminate the noise.
First wrap the pump not the motor.
the noise can be caused by many things.
Harmonics.
You can try to increase the mass of the system by bonding some type of weights to the pipes to change the natural frequency. Solidly mount the pipes hanging in the air, use rubber brackets or add gaskets to mounts. Cut the pipe on the discharge remove a section and add a flexable connector. On discharge get some soft copper pipe, and put a loop in the discharge line. Wrappping the lines in sound proofing material will probaably be of little use. Been there tried that.
I would first recommend trying to isolate the pump from the rest of the pipes. See if there’s a rubber connector available at the hardware store to go between the pump and the rest of the system. The more flexible the better. It would likely attach at each end with a hose clamp. If that’s not enough then I would look at trying to enclose the pump with a box as described above.
