Pressure tank/Accumulator

schoolbuscraig · 07-17-2022, 04:49 PM

I have looked at past posts/ threads and I didn’t get much info. How many people are using a accumulator/pressure bladder system on there bus, and how does it work? I am mid build and I am ready to set my fresh water tank and pump.

Drew Bru · 07-17-2022, 05:15 PM

We put one in right after the pump. Its not that big, smaller than a football, and it evens out the flow so the pump doesn't have to work as hard by cycling all time. If we're just using a short burst of water to rinse something off the pump doesn't even kick in it just uses the pressure in the system. Its a snap to install and they're pretty cheap so if you've got the room for it there's not really a reason not to put one in.

schoolbuscraig · 07-17-2022, 06:22 PM

Thanks for the input, I figured it can’t hurt!

Rucker · 07-18-2022, 11:39 AM

Design tip: consider mounting the pump so it does not vibrate and annoy you.

If the pump is mounted to a large, flat surface, congrats, you have built a large speaker.

I mounted my pump on its own panel, a small piece of 3/4 ply, which in turn is secured to a frame by heavy duty rubber bungees. The inlet and outlet are looped flexible lines so they also can't transmit the vibration.

Your accumulator should tee off right after the pump. If you're using a Surflo or equivalent it will pressurize the accumulator and as already mentioned, when you open a faucet it evens out the cycling of the pump, especially if you have the water going at a trickle.

djdalfaro · 07-25-2022, 07:42 AM

I should note that not all pumps accomodate an accumulator tank well. Pumps with internal bypass valves that modulate flow don't really operate well with an accumulator tank.

TheHubbardBus · 07-25-2022, 07:56 AM

Quote:

Originally Posted by djdalfaro

I should note that not all pumps accomodate an accumulator tank well. Pumps with internal bypass valves that modulate flow don't really operate well with an accumulator tank.

I'm not sure if that applies to our pump's construction (remco aquajet variable speed), but their documentation advises against using accumulator tanks as well.

Rucker · 07-25-2022, 11:29 AM

Quote:

Originally Posted by TheHubbardBus

I'm not sure if that applies to our pump's construction (remco aquajet variable speed), but their documentation advises against using accumulator tanks as well.

Good point. Apparently their sensing mechanism may get fooled by an accumulator (says at least one seller). At any rate it isn't required for this kind of variable rate pump.

It is a super powerful pump, probably good for long runs and large freshwater tanks (and lots of water usage). It draws a lot more current than the typical RV water pump.

A standard conversion probably doesn't need this much pump. 3.0 to 3.5 GPM should be fine unless you have unusually long and complicated supply pipe runs.

TheHubbardBus · 07-25-2022, 11:37 AM

Quote:

Originally Posted by Rucker

Good point. Apparently their sensing mechanism may get fooled by an accumulator (says at least one seller). At any rate it isn't required for this kind of variable rate pump.

It is a super powerful pump, probably good for long runs and large freshwater tanks (and lots of water usage). It draws a lot more current than the typical RV water pump.

A standard conversion probably doesn't need this much pump. 3.0 to 3.5 GPM should be fine unless you have unusually long and complicated supply pipe runs.

Thanks for that, Rucker. It's nice to know the 'why' of things.

FWIW, they make both a 3.4 gph & a 5+ gph (can't remember the actual figure). We got the smaller of the two. Agreed on the max amps, but I figured as a variable speed, the current draw would be proportional to the demand. Of course it'll be wired assuming max amps continuous, but I'm curious to see what it's actually pulling in use. If you have any insight into that, it would be appreciated.

Iceni John · 07-25-2022, 02:06 PM

I have a Watts DET-5 (2-gallon size) pressure accumulator tank that's fed by two SHURflo 2088 water pumps set to 45 PSI. The accumulator tank works well and completely eliminates any hunting by the pump. Typically I have only one pump in use at a time, with the other as a spare or backup, but if I needed extra flow rate I could run both at the same time. Each pump is mounted to an aluminum plate that is attached to the pumps' pull-out tray by two wing nuts, with quick-disconnect fittings for water in and out and a quick-disconnect electrical supply wire, making it an easy no-tools job to completely remove a pump in less than a minute if it ever needs servicing or repair. So far, so good.

John

Rucker · 07-25-2022, 02:28 PM

Quote:

Originally Posted by Iceni John

I have a Watts DET-5 (2-gallon size) pressure accumulator tank that's fed by two SHURflo 2088 water pumps set to 45 PSI. The accumulator tank works well and completely eliminates any hunting by the pump. Typically I have only one pump in use at a time, with the other as a spare or backup, but if I needed extra flow rate I could run both at the same time. Each pump is mounted to an aluminum plate that is attached to the pumps' pull-out tray by two wing nuts, with quick-disconnect fittings for water in and out and a quick-disconnect electrical supply wire, making it an easy no-tools job to completely remove a pump in less than a minute if it ever needs servicing or repair. So far, so good.

John

I would love to see a picture of this setup-definitely best in class design!

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