Water pump noisy...

TNGW1500SE wrote:
Interesting idea:
http://www.modmyrv.com/2009/06/10/rv-diy-water-accumulator

This is one DIY project that I don't understand. The individual parts are probably more costly than buying a small pressure tank with bladder off the shelf. Also, in my area PVC is non-code for potable water. CPVC is what is used.

Interesting idea:
http://www.modmyrv.com/2009/06/10/rv-diy-water-accumulator

I'll nod before your experience and knowledge. I noticed a lot of vibration isolation from just using soft-wall tubing vs. the rigid hose but if 15' is the formula, so be it.

westend wrote:
SG,You're an acoustician, by trade, aren't you?

Of sorts I suppose. Sound engineering for television production - studio, mobile, post production, facility design, taught college in the discipline for awhile. 45 yrs was enough though so these days I fool around with RVs. :W

A $100 water pump by it's nature vibrates and that vibration radiates out to the trailer mostly via the output hose that in most if not all cases these days connects to the trailer's hard wall PEX tubing. The trick is to dampen those vibrations with the soft wall hose before they get to the PEX so the longer the hose the better, within reason of course ... I used 25' but I suspect 15' might do it, but 3' certainly doesn't have the same effect.

SG,
In the practical sense and using your materials I don't doubt your results. However, a long length is not always needed to dissipate vibration. You're an acoustician, by trade, aren't you?

Carrier wrote:
You think a 10 or 15 foot would be as effective?

westend wrote:
Yes, absolutely. The extra 15' in Soundguy's installation does act like a reservoir so he might get one less pump cycle/day.

You only need to isolate the pump's vibrations so one or two feet of 1/2" soft vinyl tubing would do the same. You want to make sure the tubing can handle the pressure.

I originally discovered how using a long length of pump output hose dampened vibration several years ago when I was experimenting with using one of these pumps as a water transfer pump. With the pump sitting on my workbench I had (for convenience) connected a 25' length of potable water hose to the pump output for my experiment and although it had nothing to do with my water transfer project I noticed that the hose vibrated like crazy where it connected to the pump but those vibrations diminished rapidly the further along the hose I looked. Yes, my recollection is that by 15' along the hose vibrations were noticeably dampened, I only ended up using a full 25' for my own situation because I had the hose and had the space to put it in. Considering this I'd have to disagree with the statement that "one or two feet of 1/2" soft vinyl tubing would do the same" ... I'd tried that solution several times previously, including using Shurflo's so-called "pump silencer kit" which consists of two 3' long braided hoses, and that resulted in just a minor improvement. Hose length is what makes all the difference.

Carrier wrote:

You think a 10 or 15 foot would be as effective?

Yes, absolutely. The extra 15' in Soundguy's installation does act like a reservoir so he might get one less pump cycle/day.
You only need to isolate the pump's vibrations so one or two feet of 1/2" soft vinyl tubing would do the same. You want to make sure the tubing can handle the pressure.

FWIW, I just replaced some tubing on my irrigation sprayer. The cross-linked tubing gets very brittle and hard because the sprayer sees a lot of sun. I replaced some of it with 1/2" vinyl tubing. The Shurflo pump on the sprayer is almost identical to the RV models, on-demand 60 psi.

SoundGuy wrote:

Carrier wrote:
What make of hose did you use?

Unfortunately many potable water hoses sold these days are braided for strength but that also makes them very stiff. I happened to have a 25' length that wasn't braided and therefore was quite pliable so I used that instead. Since my pump is a Shurflo that uses 1/2" NPT fittings I cut the 3/4" GH ends off the hose and used screw clamps to secure SHURflo Fittings to each end of the hose. I didn't know it at the time but Shurflo now also offers a Wingnut Swivel 3/4” GHT (M) x 1/2” NPT (F) adapter that would eliminate the need to cut the GH ends off the hose and if I were to do it again that's what I'd use.

You think a 10 or 15 foot would be as effective?

The only place we can tell when our relocated pump is running is right where the photo was taken from. The pump is mounted on four layers of foam mouse pad, and the grey inlet hose loop is 24" long while the white outlet hose loop is 40" long. Not shown is the 2-gallon accumulator tank that drastically reduces the number of pump cycles. The pump was originally installed in a cabinet next to the bed...

Searching_Ut wrote:
My water pump put many truck jake brakes to shame noise wise. I ended up using rubber anti fatigue floor mat chunk under pump, ran flex hose from output to an accumulator tank then again flex line between tank and trailer hard plastic tubing. I also used insulation tubing in a couple areas to make system virtually noise free.

This is what I did. The pump is so quiet now that we didn't hear it empty the FW tank through a leaking low point drain while we were lunching at a rest area. (Hint - don't make it too quiet!)