Noisy water pump - making it quieter

[ShrimpBurrito]

Originally Posted by brulaz

Another irritating issue. I mentioned earlier that the water pump was noisy. Finally got around to reading the Shurflo installation and operating manual and it says: "The pumps ports/strainer *should not* be connected to plastic or rigid pipe. The pump's normal vibration may transmit through rigid plumbing causing noise, and possibly loosen or crack components."

Well guess what? While on the tank side of the pump Trailmanor used a nice, soft plastic tubing with braid reinforcement, on the other side the pump is attached directly to the hard plastic plumbing used throughout the rest of the water system. I bet that's where the noise is coming from. All they needed to do was put about a foot of the soft stuff between the pump and city water input tee. What were they thinking? I guess they just weren't.

I have a fair amount experience with the water pump. And in fact, I have an identical model as in the TM that I use as a water transfer pump, as it actually used to be installed in my TM where it made a racket. When held in my hand, the pump I use as a transfer pump is not quiet silent, but very quiet, when in use. The difference? Yes, if you replace the PEX with flexible reinforced tubing, that will do alot to reduce the noise. But be careful not to create new high points in the plumbing that would prevent water draining when you open the drain valves. That is my guess as to why TM doesn't use flex tubing -- the high points are harder to control.

It would also be of great benefit if you mount the pump to a shock absorbing pad -- something like a thin sheets of plywood with a piece of semi-rigid foam or rubber in between. The one sheet is mounted to the wall, and the pump is mounted to the other sheet. The screws mounting the pump should not extend far into the foam, as they will transmit the vibration.

If you do these 2 things, your water pump will be VERY quiet.

Dave

Originally Posted by ShrimpBurrito

... be careful not to create new high points in the plumbing that would prevent water draining when you open the drain valves. That is my guess as to why TM doesn't use flex tubing -- the high points are harder to control.

It would also be of great benefit if you mount the pump to a shock absorbing pad -- something like a thin sheets of plywood with a piece of semi-rigid foam or rubber in between. The one sheet is mounted to the wall, and the pump is mounted to the other sheet. The screws mounting the pump should not extend far into the foam, as they will transmit the vibration.

If you do these 2 things, your water pump will be VERY quiet.

Thanks Dave.

There is only a very short section (~1') of horizontal hard plastic tubing between the pump and the tee to City water. So I don't think it would be difficult to fit some soft plastic tubing there that would not sag. Anyway I'll make sure it doesn't. And no, I don't think it was a deliberate design decision on Trailmanor's part. I think it was an oversight.

The pump is already mounted on rubber feet and then on some sort of shock pad. I can't get to it right now, but will look more closely later in the week.

Anyway, it's good to hear that this can be easily fixed.

Bruce

[ShrimpBurrito]

Originally Posted by brulaz

There is only a very short section (~1') of horizontal hard plastic tubing between the pump and the tee to City water. So I don't think it would be difficult to fit some soft plastic tubing there that would not sag. Anyway I'll make sure it doesn't.

Replacing 1' of PEX with 1' of reinforced (make sure you get reinforced) plastic tubing will definitely help, but ideally, you'd want to make a loop in the tubing, making it maybe 3' long. The loop will absorb the vibrations better than a straight 1' section. If you do that, be careful you don't create any low points if you want to continue using the gravity drains.

The pump is already mounted on rubber feet and then on some sort of shock pad. I can't get to it right now, but will look more closely later in the week.

Those rubber feet help, but they are not enough for the pump to achieve quiet operation. The real problem is the screws -- they are connected to the pump and the wall/mounting surface, and transmit the vibrations directly to the TM wall (or wherever it is mounted), which in turn vibrates everything on earth. You need to interrupt that transmission so that whatever means you use to mount the pump assembly as a whole does not touch the pump. That's where the plywood-foam-plywood sandwich comes in, and that's why it's important that you use 2 sets of screws -- one set to mount the entire assembly to the wall by going through the one sheet of plywood, and another set to mount the pump to the other sheet of plywood.

It's easy to see the pump's quiet potential -- disconnect the plumbing, unscrew the 4 mounting screws, and turn it on. It's not an impeller pump, and in fact has little moving parts, so you can run it dry without any problems. You'll hear more noise than you would if it were pumping water through flexible tubing, as you'll hear air coming out of the intake/outtake ports which ordinarily would carry water, but I guarantee you it will be much quieter than now. The biggest difference you'll notice is that the noise you do hear is isolated to the pump itself, and you'll realize how much of the noise you hear in the trailer is actually transmitted noise.

Dave

Originally Posted by rumbleweed

Use a 2 or 3 foot square piece of 3/8 ply and glue carpet to the bottom side.

I've got some scraps of 2" rigid insulation foam that could be used as well. I'll try that.

One of the things we want to do with the Elkmont is spend a lot of time dry camping. That means using the battery, the pump and the propane furnace, frig and water heater more than usual.

One our initial problems was how noisy the 12 V Shurflo pump was. In part that was because it did not have flexible tubing installed on both sides, but only between the pump and the tank.

So I finally got around to following ShrimpBurrito's advice and added 3' of flexible, reinforced 1/2" I.D. tubing between the noisy pump and the hard PEX stuff.

Fairly simple modification. Unscrewed the pump from the PEX and added a straight, male 3/4" pipe to 1/2" I.D. hose adapter to the PEX end. To the pump end added a 90 degree angle, female 3/4" pipe 1/2" I.D. hose adapter. Used teflon tape on the threads. Soaked the hose ends in hot water then pushed them on and clamped.

From the PEX end, the hose runs horizontally (it seems to drain ok, but I'll probably check each winter) behind the pump into the furnace area and then through a small hole in the partition back into the battery compartment and to adapter at the pump. It's not close enough to the furnace for that to be an issue. I'll be adding bits of foam where the hose touches stuff and will post a picture when I get my camera back.

This mod really cuts the pump noise. The pump itself is already mounted on a rubber/flexible support, so I didn't add anything more there.

The next plumbing project is putting a 2 gal pressure tank under the bottom shelf in the rear, passenger side corner.

[ShrimpBurrito]

Excellent! If later on down the line you find you want to quiet the pump even more, you can always add the foam mounting pad, but adding the tubing is a major improvement IMHO. Of course, now it's easier on the ear to let the water run freely!

The pressure tank is also a welcome mod. If I had room for a 2 gallon unit, I would have installed it, but since I'm super tight on space, I put in a ~22 oz unit. It definitely cuts down on cycling, but obviously the bigger the better in this case, so the 2 gal unit should be great. Let us know how it turns out.

BTW - if you need to tie into PEX at some point and don't have a crimp tool, the Sharkbite connectors work perfect, as advertised. So far, no leaks.

Dave

If money is not an issue but space and noise are, you can try one of the micro-controller controlled pumps. When needed, they run continuously at a variable speed to eliminate the pulsing sounds.

Originally Posted by ShrimpBurrito

BTW - if you need to tie into PEX at some point and don't have a crimp tool, the Sharkbite connectors work perfect, as advertised. So far, no leaks.

Oh! Too late though, I've already forked out $35 for a crimping tool. Didn't need it for the flexible tubing install, but will for putting in a T for the tank.

Who knows it may be useful around the house too. All the plumbing I've done there is copper, but I'm getting tire of burning my fingers.

Okay, I have some questions for Lesherp, ShrimBurrito, brulaz, thepair, so I figured I'd just post a reply, and also just in case anyone else has a similar question to mine you can hopefully have it answered in this forum. As reference, I have a 2720 (standard with the pump and fresh water tank under the dining table seat).

1. Is 1/2" ID 3/4" OD reinforced flex tubing correct? I ask because a) it looks larger than the flex that TM used going from the fresh water tank to the pump and b) The black screw adapters from the parts list of thepair's ultimate water transfer bridge do not slip on (so it seems the OD is too big)

2. Are the fittings needed to replace the PEX with flex tube (to quiet the pump) something you can get at the hardware store, or do you have to get it from iplumb.tv? I have seen descriptions of what to use, but wasn't sure if it is sharkbite, flair it, or what.

I have a transfer bridge built, but it is actually a little harder to install on a standard 2720 (in a way). There is plenty of room to work, however there is a very short run from the city water line in, so no room to directly cut into the PEX like most of the users here have done. I think I will have to cut into that line, but then put an adapter and run some more flex to connect up the other side. (see picture attached).

Any help or suggestions would be appreciated. Thank you all for your help and insight.

[ThePair]

Originally Posted by Mike_M

Okay, I have some questions for Lesherp, ShrimBurrito, brulaz, thepair, so I figured I'd just post a reply, and also just in case anyone else has a similar question to mine you can hopefully have it answered in this forum. As reference, I have a 2720 (standard with the pump and fresh water tank under the dining table seat).

1. Is 1/2" ID 3/4" OD reinforced flex tubing correct? I ask because a) it looks larger than the flex that TM used going from the fresh water tank to the pump and b) The black screw adapters from the parts list of thepair's ultimate water transfer bridge do not slip on (so it seems the OD is too big)

2. Are the fittings needed to replace the PEX with flex tube (to quiet the pump) something you can get at the hardware store, or do you have to get it from iplumb.tv? I have seen descriptions of what to use, but wasn't sure if it is sharkbite, flair it, or what.

I have a transfer bridge built, but it is actually a little harder to install on a standard 2720 (in a way). There is plenty of room to work, however there is a very short run from the city water line in, so no room to directly cut into the PEX like most of the users here have done. I think I will have to cut into that line, but then put an adapter and run some more flex to connect up the other side. (see picture attached).

Any help or suggestions would be appreciated. Thank you all for your help and insight.

Let's see what I can answer:

1) Dunno for sure, because I haven't tried to do the whole "noise reduction" thing. I do think that it is 1/2" ID, just like the PEX tubing. By the way, the black flex-tube adapters, that go into the tube? I never bothered using the inserts--I couldn't get them into the tubing, either. I just used the gray screws (to replace the white ones that come with the 3-ways) for the flex tubing. I threw away the inner, black tube adapters. Never had a leak or problem so far, so I think it's safe

2) You may be able to find a fitting that goes from PEX to barbed end (for the flex tubing) at your local HW store, and then use a hose clamp and make the connection that way. Should work just as well. The only reason I used the flair-it was because it was a 3-way, and then I used that flex-adapter kit (only the nut, as above) and it worked fine. But, to just replace a piece of PEX with a hose, a barbed end + hose clamp should work fine.

3) Yes, I agree it looks like the geometry of your setup is sufficiently different that you'll probably be best off running flex tubing for the sides, to make everything connect. You'll end up with a floating bridge, but it will still functionally work. I'd imagine you'll end up removing that elbow, and just hooking into the vertical pipe with one flex tube, and butting another into the city water inlet. If you plan on doing it this way, you can make sure to leave enough stub to get your connections solid (with a PEX/barb connecter, or whatever you find).