Using a standpipe as an accumulator?

[SilvrSausage]

I'm wondering if anyone has ever tried using a standpipe instead of an accumulator to damp water pump pulses. A standpipe consists of a vertical piece as large of a diameter pipe as possible, and as tall as possible, capped on the top with the bottom teed into the water system. The principle is, air in the pipe compresses and forms a "cushion" in the system to damp pulses and provide a small pressure reserve between pulses during slow flow.

The advantage of using this is it can be incorporated into the wall, as opposed to an accumulator tank, which takes up precious cubic inches inside the trailer.

Has anyone ever tried this?

-SilverSausage

[Kevbo10]

mr sausage,

why not just use a SHURflo Smart Sensor 4.0?

you won't need anything but.

just sayin.

tanked

[SilvrSausage]

Fair enough question. I happen to be in the middle of a panels-off restoration, so it would be easy and very cheap to put a piece or two of pipe in a convenient wall while I am at it, as opposed to a bulky accumulator.

As far as a better pump, I'm looking at under $10 worth of pipe, versus $75 to 150+ for the better pumps out there. The budget has already gotten kind of out of hand on this project, but I do intend to upgrade to a nice pump like that someday, perhaps when the one I have breaks.

It might be sooner though, especially if the standpipe idea doesn't help any... this pulse pump knocks like it is there to serve a warrant!

-SilverSausage

[Kevbo10]

Originally Posted by SilvrSausage

Fair enough question. I happen to be in the middle of a panels-off restoration, so it would be easy and very cheap to put a piece or two of pipe in a convenient wall while I am at it, as opposed to a bulky accumulator.

As far as a better pump, I'm looking at under $10 worth of pipe, versus $75 to 150+ for the better pumps out there. The budget has already gotten kind of out of hand on this project, but I do intend to upgrade to a nice pump like that someday, perhaps when the one I have breaks.

It might be sooner though, especially if the standpipe idea doesn't help any... this pulse pump knocks like it is there to serve a warrant!

-SilverSausage

mr sausage,

you're a contrast of ideas.

you want long hot showers, i'll assume w/ some amount of pressure, and you're boondocking, but don't wanna spend an extra 50 bux for:

no hammering
50psi
flow rate of 4gpm

you're correct, go w/ what you have and a pc of pipe.

yours,

bent w. lee

[SilvrSausage]

Contrast of ideas? Actually, I'm more the wizard of ideas few seem to have tried before. Some of my grandiose ideas work out surprisingly well. Others... not so much.

My setup is such that the primary water tank and everything including the standpipe would be within the insulated shell; an accumulator would use cabinet space, the standpipe, none. I can locate supplemental water tanks under the floor for long showers when freezing is not a concern (most of the year in So. Cal, but I do go on winter camping trips in the local mountains.) As a year-round part of the water system, the damping device can't go down there despite the extra space, you see.
-SilverSausage

[rseagle]

Camping World sells a FloJet RV High Volume Water Pressure System (#13247) that includes the pump, strainer and an integrated 1.2 gal accumulator tank. I'd feel more comfortable investing in one of those than what you're proposing.

[Jim Clark]

Originally Posted by SilvrSausage

I'm wondering if anyone has ever tried using a standpipe instead of an accumulator to damp water pump pulses. A standpipe consists of a vertical piece as large of a diameter pipe as possible, and as tall as possible, capped on the top with the bottom teed into the water system. The principle is, air in the pipe compresses and forms a "cushion" in the system to damp pulses and provide a small pressure reserve between pulses during slow flow.

The advantage of using this is it can be incorporated into the wall, as opposed to an accumulator tank, which takes up precious cubic inches inside the trailer.

Has anyone ever tried this?

-SilverSausage

It is what I would do. Saves time and money.

[Royce]

Originally Posted by SilvrSausage

I'm wondering if anyone has ever tried using a standpipe instead of an accumulator to damp water pump pulses. ... ... provide a small pressure reserve between pulses during slow flow. ...

-SilverSausage

If you take that approach, be sure to provide a method of airing the standpipe. they will slowly fill with water and quit working if you cannot refill with air. That can be accomplished wiith a valve stem added to the top of the standpipe or you can re-air by draining the system. Of course you may want to consider placing in in an interior wall to provide a measure of 3 season use anyway. You most likely thought of that.

I don't think they will do much to dampen the pump pulses or quiet the pump, just increase the time between pump turn on and off while running a slow stream.

[Buttercup]

I don't think they will do much to dampen the pump pulses or quiet the pump, just increase the time between pump turn on and off while running a slow stream.

And that will shorten pump life - the pump will be running longer periods of time under greater load - this could lead to early winding failure.

[53flyingcloud]

SilvrSausage,
Curious mind..
You might want to change your profile from..."currently looking to......whatever the unit you now own..."
Interesting topics..BTW, when boon-docking, Wally used the simplest approach..Just dig a hole out back and, let it go back to nature's bio..

Works..but, not legal..

[klattu]

Originally Posted by SilvrSausage

I'm wondering if anyone has ever tried using a standpipe instead of an accumulator to damp water pump pulses. A standpipe consists of a vertical piece as large of a diameter pipe as possible, and as tall as possible, capped on the top with the bottom teed into the water system. The principle is, air in the pipe compresses and forms a "cushion" in the system to damp pulses and provide a small pressure reserve between pulses during slow flow.

The advantage of using this is it can be incorporated into the wall, as opposed to an accumulator tank, which takes up precious cubic inches inside the trailer.

Has anyone ever tried this?

-SilverSausage

Yes,
It works great.
Will really help if your having the hammer at turn off.
And it 'recharges' at each drainage.
Your idea is used by many plumbers, as I see it often at the end of a long run.
Most times it is a same size of pipe.
Your going to a upsize would be even better.

[Excella CM]

You can increase the capacity of a damper/accumulator by using a bell reducer to a larger size tubing- say 1" or greater.

[clancy_boy]

Originally Posted by SilvrSausage

I'm wondering if anyone has ever tried using a standpipe instead of an accumulator to damp water pump pulses. A standpipe consists of a vertical piece as large of a diameter pipe as possible, and as tall as possible, capped on the top with the bottom teed into the water system. The principle is, air in the pipe compresses and forms a "cushion" in the system to damp pulses and provide a small pressure reserve between pulses during slow flow.

The advantage of using this is it can be incorporated into the wall, as opposed to an accumulator tank, which takes up precious cubic inches inside the trailer.

Has anyone ever tried this?

-SilverSausage

There are purpose built stand pipe or "water hammer" damping devices sold in the plumbing departments of most big box home stores They are generally a little larger then the diameter of the pipe you will be attaching it to I have one in my garage at the sink - it's one inch in diameter and 18" long attached to 1/2" copper pipe. It has a rubber bladder which compresses when hit with a slam of a shut of in the water system. The rubber bladder eliminates the need for air entrapment by draining. Really quiets the plumbing but would have no effect to reduce water pump cycling in a trailer - not enough bladder volume like an accumulator.

[Crusty]

I did this very thing at a house I once owned which had water hammer issues and it soved the problem. The downside though was that after a while the air bubble traped in the column under pressure would eventually dissolve into the water and leave the standpipe full of water and ineffective as a hydraulic shock absorber. I put a valve in the top of the pipe which I could open when the water pressure was relieved to admit some more air.