Fresh water pump noise

Dec 1, 2020
129
CAL 27 Illahee / Brownsville WA
Hello all,

I have flushed and sanitized the fresh water system in the old Cal, but the noise of the pump seems pretty loud. The pump image is here:

1632718623056.png


The video with the pump starting and stopping is at this link: Sailboat Shared

The boat is small, only 27 feet so that may be part of the issue, but it seem pretty loud inside the boat.

Thoughts?
 

DougM

.
Jul 24, 2005
2,242
Beneteau 323 Manistee, MI
Seems like thats normal. The pump may be somewhat noisier simply because its older. The pumps in my boat were noisy from day one, an could be heard even though they were either under a cabinet, or behind a settee.
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
Sounds a little loud, but not excessively so. Pump noise will vary because of how it is mounted, what it is mounted on, and where it is mounted. Usually pumps are mounted on some kind of rubber feet that helps to keep the noise from reverberating. A pump in an empty cabinet will also sound louder because there is nothing to absorb the noise or break up the sound waves.
 
Sep 26, 2008
546
Hunter 340 0 Wickford, RI
On my 340 the pump in located under the seat at the center table, just in front of my water heater. There is no insulation in this area and in it does sound loud. But no louder than yours does. Lots of room for echo in there. It’s mounted on rubber feet (as dlochner has described) and I placed a soft foam pad between it and the bulkhead. It quiets it somewhat but not completely.
My water comes out a little faster than yours does, but that’s GPM sizing.
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
The pump noise is the pump cycling. The cycling is caused by the pump's built-in pressure switch that kicks the pump on when the pressure drops below a preset pressure of ~20 psig the pump turns on automatically to bring pressure up to its preset pressure, typically 40 psig. An accumulator on the pump discharge could mitigate the cycling.
 
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Dec 1, 2020
129
CAL 27 Illahee / Brownsville WA
Do any of you have a variable speed pump or "heard" one in action on another persons boat? I see something like this on Amazon and wonder if it's any quieter.

1632788290561.png
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
Diagphragm pumps are inherently noisy when compared to vane style pumps because of their design. In their simplest form there is a piston that moves a "rubber" diaphragm back and forth to pump water. That is what causes the hammering sound. Vane pumps make a whirring sound as the vane spins.

The advantage to diaphragm pumps is that they both push fluid and suck fluid making them self-priming, vane pumps can only push fluid rendering them to be unable to self-prime so they would have to be below the level of the water tank.
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
The Seaflow 42-series pump 42-Series Diaphragm Water Pumps - SeaFresh Marine - An Authorized SEAFLO Dealer has a built-in pressure switch that automatically starts and stops pump when faucet is opened and closed just like the . They claim there is no need for an accumulator tank and no pump cycling. I have a Jabsco diaphram pumps that also has a pressure switch that turns the pump on when the pressure drops to 20 psig without an accumulator tank and minimum cycling.
 
Jan 7, 2011
4,727
Oday 322 East Chicago, IN
Sounds a little loud, but then again, so did the water running in the sink.

good news is that it appears your accumulator tank works.

you can check to see where the pump is mounted…if on a hollow piece of wood or fiberglass, it could be made quieter by using some rubber pads under the mounting feet or moving to a more solid mounting place.

but, I would not replace it (if you do, send me the old one)…

Greg
 
Dec 1, 2020
129
CAL 27 Illahee / Brownsville WA
It’s mounted upside down to the plywood in the vee berth in a space next to the water tank. A bitch location to access to determine if the feet have rubber vibration isolation installed.