Dear Dave,
My RV’s water pump was very noisy so I replaced it with a Quiet Pump, with no change. I still have the water hummer noise. What do you suggest? —Donald, 2019 Greyhawk
Dear Donald,
Most manufacturers use the Shurflo water pump, which is actually owned by Pentair. Shurflo has several models ranging in price from the inexpensive model 4008 all the way up to the Ultra Quiet and High Flow model EZNTP-10-0115, which costs more than $200. I’m not sure what model you replaced the original one with; however, you found out the hard way that it’s usually not the pump that is making the noise.
Where the noise from the water pump is actually coming from
When I was at Winnebago, we did extensive research on getting the thumps and vibrations out of the water pump long before Shurflo and others came out with quiet models. Most of the noise coming from a water pump is actually vibration resonating through the compartment or walls. From some of the videos I researched, it looks like your water pump is mounted inside the rig in a compartment. If it is mounted against the wall, or on the floor, the vibration which you will get in even the quietest pump will be amplified by the wood, especially if it is mounted to a plywood wall.
The first thing I would suggest is to isolate the pump on a horizontal surface and mount it on something that will insulate the sound. We used a piece of the sidewall material from a window cut out. It was block foam insulation sandwiched by plywood. You can find a similar material from Owens Corning and others. You may even want to find a hard rubber pad to place it on. Either way, even though most pumps have rubber feet, they need to get up off the floor or away from the wall.
The next step would be to change the hard plastic pipes coming in and out of the pump, as they will also provide thumping. You can make your own using 1/2” ID plastic piping and fittings from a home improvement store. Also, Shurflo has a ready-made kit available on Amazon here.
You can also insulate the pipe even more with water pipe insulation tubes, especially covering the hard plastic or copper fittings. And if the water lines go through a cutout in the wall or floor, insulate that, as well.
Another option is to relocate it to the basement compartment if it is heated. With easy to cut PEX tubing and compression fittings, DIY plumbing work is easy.
You could get an accumulator tank
An accumulator tank is an auxiliary tank that holds water and is pressurized by an internal bladder which reduces cycling of the pump. You can find several models like this one from Shurflo here.
You might also enjoy this from Dave
Why does my water pump cycle every few seconds?
Dear Dave,
Thanks for joining RV Travel – I’ve really enjoyed your columns. My question: We have a 2018 Thor Freedom Elite on a Ford E-350 chassis. It has a Shurflo 4008-101-A65 water pump rated at 3 gpm and 55 psi. The pump pumps fine with plenty of flow. The problem: When there is no demand for water, about every 10 – 15 seconds, the pump “burps” or cycles for about one second. I have found no leaks or evidence thereof and no faucets or the toilet are leaking.
While there is no problem with leaks or water delivery, it is kind of annoying. Any suggestions? Thanks. —Don
Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”
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Thanks for the info and suggestions Dave…
The pump in our Winnie Class A was so loud it was audible about 15′ away – outside! Inside it was worse. It was mounted in the rear and right in the middle of a narrow storage bay – next to the water tank and virtually inaccessible – except by our 4 year old great grandson! I removed it and mounted it on a piece of 3/4″ plywood, with rubber pads between it and the floor and rubber pads under the rubber feet of the pump. It is now at the edge of the compartment next to the water tank. The only problem now is I cannot hear when it is running – so I have to go check the lite on the panel over the range! Pics available!
I experienced the same thing and found another solution. I purchased a fairly new product. It is IRVWPC. You can find more about it here https://www.irvwpc.com/. This is a fairly easy install and reduces the hammer on the pump to almost nothing. We are very happy with this product.