[Blue Frog Systems]

Have posted about this before and gave up on it... thought i would have another try last night.

I have my RO set up with a shurflo pump between the pre filters and membranes. Im running two 75GPD membranes parralel and the shurflo pump from a car battery.

The pump isnt flowing constantly. Its doing a few seconds, then sounds like its switching itself off for a second and then back on again (the vibrations make a right noise). This only happens when the battery is fully charged and as it gets lower on power it stops jumping.

Now i have spoken to a supplier about using the shurflo 100psi as a booster. The guy told me that he uses 100psi pumps when making his RO's. Problem is that it makes this god damm awful noise.

Its like the car battery is too powerful to start with.

can anyone suggest something to get it to flow right and not make the vibrating noise ?

Quick drawing of how my system is set up.... I should have been an artist

[EZclean]

you may need to run the membranes in series ( 1 feeding the other) if your running 1 pump as opposed to parallel, or it could be a pipe plumbed incorrectly.

[Blue Frog Systems]

tried running one after the other but the flow slowed down. Will have a look at the plumbing later but im 99.9% certain its correct.

Keep em coming guys

[john tomkins]

I use a 100psi Shurflo with my 200gpd RO, using the pump on its own soon builds up too much pressure for the small pipes and the pressure switch kicks in till the pressure drops and the pump starts again(which is what you are getting) I fixed it by adding a spare Varistream I had lying around, set it up to constant 80/90 psi and it runs fine now.

[Blue Frog Systems]

You got another spare varistream lying around by any chance John ?

[Glass Cleaner]

Can you not turn the booster down?

Isnt there a small allen nut on the front of the pump bearing housing?


Also why are you running it off a car battery? Are they designed to be powered this way? Can you not run an extension cable out to it?

[Blue Frog Systems]

The allen bolt at the top doesn't do much at all... There are pozzy screws up there aswell, but they seem to be holding the parts together.

I'm running it off a car battery as its 12V. I asked about putting a plug on it, but was told in my thread about this a few months back that I have to run it off a battery.

[ftp]

Noise is normally a sign of air in the pump - get it as low as you can and check all the seals on connectors/jubilee clips. I would think the pressure switch is shutting it down every few minutes. I've never seen a system in parallel before.

[NWH]

You need to run a 40x40 with it,far to much pressure for that membrane.

[DanielUK]

Couldn't you get a 240v - 12v DC converter from Maplins instead of using the car battery?