So I got all my stuff together to quiet the pump down and smooth out the flow. The little ShurFlo accumulator tank is pumped with 40 psig of air. It is hooked up to the pump with 1/2"X36" flexible hose with 1/2 Female Pipe Threads(FPT), and from the accumulator tank to the Pex with another 1/2"X36". The accumulator accepts 1/2" FPT, the pump accepts 1/2" FPT and the Pex water line accepts 1/2 FPT. That made it easy to hook up. I could have used a shorter flex line for the hook up but I figured the total 6' of soft pipe would dull the pump. To further help take the harshness out the pump running I glued(PL-400 subfloor glue) a piece of 1/2 wood to a 1" thick piece of ergo-mat the screwed the pump to the wood, then glued it to the floor with a dob, 'bout the size of a quarter of the PL400 on each corner of the ergo-mat. That way if I had to, I could get it back off. This little mod really made a difference. The pump is not silent, but is very quiet. The water flow is real steady even on low flow. the water that comes out of my filter faucet(dual stage under-sink)is much more steady too. When I ordered my accumulator tanks, my intention was to install one just like you see and the other one downstream of the under-sink filter to help out the flow with that little dude. Not really sure I need it now. I have a pretty good amount of room under the sink, behind the drawers and around the water heater. So I may just put the other one on the "shelf of things to do" and install it later on. I would be real easy to install it if I get around to it. It would be equally easy to yank it if it doesn't work out.

yes, a very good mod IMHO. I did similar and well worth the effort.

Vintage465 wrote:So I got all my stuff together to quiet the pump down and smooth out the flow. The key to a more quiet running pump is to ISOLATE it from the body of the RV. It looks like you did that both with the "motor mounts" on the feet AND the rubber pad on the bottom. Excellent.A mistake often made is to crank down the mounting bolts too tight so that the vibrations are then transmitted through the bolts.

Nice job! That pump should be real quiet. I had the room so I installed a 2-gallon residential expansion tank.

mbopp wrote:Nice job! That pump should be real quiet. I had the room so I installed a 2-gallon residential expansion tank.I have actually thought about using the larger accumulation tank, but in reality for our use I think the larger tank would be overkill. However, if we actually started using our shower for something other than storage and a coat rack...........this could be logical.

Vintage465 wrote:mbopp wrote:Nice job! That pump should be real quiet. I had the room so I installed a 2-gallon residential expansion tank.I have actually thought about using the larger accumulation tank, but in reality for our use I think the larger tank would be overkill. However, if we actually started using our shower for something other than storage and a coat rack...........this could be logical.Furthering that thought...........A two gallon tank would add two gallons of fresh water capacity...............

Pump Silencing & Accumulator | Good Sam Community

Vintage465
Nomad
Jun 14, 2017
time2roll wrote:
Looks great. I mounted mine on some closed cell foam used for shipping.

If those flex lines rub on anything consider some foam pipe insulation to wrap them. Provides a cushion to prevent vibrating against a sounding board.

I fastened the flex with the "mountable zip-ties". Just went out and listened to it again..........real quiet and smooth. Can't imagine why I would need it any quieter.
Sunbrook279
Explorer
Nov 25, 2022
I have ordered an accumulator. Should its pressure be higher or lower than pump pressure? Im guessing higher? thanks for inputs!
Boon_Docker
Explorer III
Nov 25, 2022
Sunbrook279 wrote:
I have ordered an accumulator. Should its pressure be higher or lower than pump pressure? Im guessing higher? thanks for inputs!

The accumulator pressure should be set at the same PSI as the pump start up pressure.

Example: If pump starts at 30 PSI then set the accumulator pressure at 30 PSI.
Bobbo
Explorer II
Nov 26, 2022
At, or possibly 1 PSI higher than, the pump cut on pressure. If you go less than the cut on pressure, the accumulator will not completely empty so you are reducing its effective volume.
profdant139
Explorer II
Nov 27, 2022
Very nice job on the installation, and a good write-up, too!

I've found that after taking my trailer to high elevations (above 9000 feet), the accumulator sometimes loses pressure and does not function properly. So I bring a small bicycle pump with us. It is easy to restore the pressure to 30 psi (which is the recommended psi for our very small accumulator).
EMD360
Explorer
Nov 27, 2022
I replaced an old accumulator with a one gallon in our old RV. The pump was already nicely isolated. I’ve been thinking about installing it in our new RV. The pump is really loud when it runs. This 25b is closer to total weight though and the tank would be on the rear axle. So using the little one again seems to make sense. I have a lot of projects one winter is over!
deltabravo
Nomad
Nov 29, 2022
HOLY THREAD RESURRECTION BATMAN!
Someone revived this 5 year old thread.

It has good info though, so I might as well add to it.

I've been using accumulator tanks in all my RVs since 2004 or so.
It evens out the flow of water on low flow situations and prevent the pump from constantly cycling on/off/on during low flow.

I also added some pipe insulation to quiet my water system.

Quieting my RV Water System with foam pipe insulation
Vintage465
Nomad
Nov 30, 2022
Wow! As I was scrolling thru the topics I see this post.......thinking, that's just like the post I did years ago! Still working perfectly at nearly six years, never check or adjusted pressure. Still a nice even, non pulsing flow at low volume settings on the faucet.
Dusty_R
Explorer
Nov 30, 2022
I've done that also. Now the pump does not run every time the toilet is flushed.

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