Accumulator, silencing hoses, or both?

[Second_Chance]

The noise from our fresh water pump seems to come and go based on how the Pex lines end up shifting after particularly rough road days. I've installed foam pipe insulation and tried to secure water lines away from walls and bulkheads, but things can still be pretty noisy at times. Searching the forum, responses seem to fall on both sides of the fence - some swear that the tank is the way to go while others say the tank is useless and the silencer hose kit is the only answer. Am I off base concluding that, given the noise seems to be vibration-based, the silencer hose kit is the right solution?

Thanks!

Rob

[Veebyes]

Just a thought. Mount the pump on a small bit of plywood. Use some bubble wrap sheet between plywood & mounting surface.

Here in Bermuda each home has its own independent water supply. The pressure system is like an RV but on a large scale. A shallow well pump takes the water from the under house tank & pumps to a pressure tank which is nothing more than a large accumulator tank.

Over time water absorbs air & the system gets 'waterlogged' with very little air left in the top of the tank for the pump to compress. The result is the pump runs for a short period everytime a tap is turned on.

In an RV application the bigger the accumulator tank the better. The larger the air bubble inside the less the pump will run at the slightest turn of the tap. The less hammer effect from the pump too.

[Second_Chance]

Thanks for the responses, everyone. One of the first things I did when we got the RV was to construct a foam & plywood "sandwich" on which to mount the water pump. It didn't make as much difference as I had hoped it would. I've put foam insulation on the Pex lines and used large cable ties to try to hold Pex lines away from walls and structures (this is the basement of a fifth wheel). Based on everyone's responses, I think I'll try the flex lines next - they're the least expensive and easiest to install - and go from there. Thanks again!

Rob

[Isaac-1]

I mounted an accumulator tank under my bathroom sink. It was a simple matter of getting a T to connect to the 2.5 gallon accumulator tank (I used a dual outlet cut off valve with a couple of pipe nipples just because it was cheapest along with a couple of section of 1/2 inch to 1/2 inch hose to extend to and from the faucet). Some people will tell you the accumulator must be closer to the pump to effect the sound, but in my experience even having the accumulator probably 7-8 line feet away from the pump it made things much quieter.

There is a scharader valve on the tank and it must be recharged with air from time to time if air leaks out, but that is no more difficult than maintaining air in tires. Exact optimum pressure will depend on your pressurizing pump,but 25-30 psi when the pump is turned off and pressure bled from the system should be in the right ballpark for most people, it is better to have too low of accumulator tank pressure than too high, the optimal amount depends on the pump model and its pressure switch. Having the pressure in the accumulator tank a little low as long as it is not zero pressure will just reduce its capacity a bit, having it too high will keep it from working at all.

[MudChucker]

Get some pipe insulation and slip it over the the pex where ever you see it touch anything...the pump itself is near silent.

An expansion/pressure/accumulator does nothing to to prevent rattles in the pipes, only prevents water hammer and the need for an air pocket in the hot water tank .

[time2roll]

If your pump connects direct to the hard pipe then yes some flex line will be a big help. No need for an RV kit as all the stuff can be obtained at a common hardware store in the length you need.

I also mounted my pump on some closed cell foam. Still makes noise but not near as much.

Besides that IMO every closed water system should have at least a small expansion tank.

[ScottG]

one_strange_texan wrote:
In my experience, accumulators need a gas charge such as from compressed air or nitrogen. Is that the case here?

You are correct.

[Shadow_Catcher]

My pump sound was transmitted through the pump mounts to the floor. The Flojet has rubber feet/mounts but they are stiff and transmit a Lot of vibration to a sounding board (the floor). I found bubble isolation mounts on Ebay which go between the pump feet and the floor.

[one_strange_tex]

In my experience, accumulators need a gas charge such as from compressed air or nitrogen. Is that the case here?

[GordonThree]

Tank didn't do anything to quiet my pump, which lives under the bed. It did solve the water hammer effect from running a faucet at low volumes.

[pianotuna]

Hi Rob,

The pump makes the noise. Isolate it and make sure the hoses have loops in them.

An accumulator tank may allow longer but less frequent run times.

[fnswhitfield]

I had the same problem. Seemed like the bathroom sink faucets, located near the pump, were going to jump out of the trailer. I installed an accumulator tank and now you can't hardly tell the pump is running. I'm a big fan of these tanks, and have used them on boats as well.They just give the pump some air cushion to pump against, rather than a closed valve and fairly rigid tubing. I have never worried about precharging them with air.
Good luck