Replacing the low pressure pump - any suggestions?

[danno]

I have a 3/4 hp Isochem magnetic pump now - It's a great pump, but only designed to max at about 20 PSI. My problem is with the low pressures, my filter between the low preesure and high pressure pumps clog pretty quickly. Also, I have to drop my low pressure cut off switch pretty darn low as I'm working with pretty low pressures in the first place. When starting the RO, it also takes awhile to build enough pressure to keep the pumps on.

What are good high and low pressure settings? 60 - 20?

Anybody have any suggestions of a good pump at a decent price?

Would this work?
http://www.ebay.com/itm/GOULDS-PUMP-CENTRIFUGAL-WATER-PUMP-1-1-4-115-230-1-PH-STAINLESS-STEEL-NOB-/110761770931?pt=BI_Pumps&hash=item19c9ea7fb3

[Bucket Head]

That pump might be better than what you have now. Can you find out any specs. on it? Maybe your local plumbing supply could give you an idea on what that pump is capable of. Get a model number and research it if you can.

I don't know what the cost of it would be, but the feed pump on mine is a Grundfos, 1h.p., 220v, with a 1" inlet and outlet. I am unsure of the p.s.i. it develops or the minimum p.s.i. my RO requires. For comparison, my high pressure pump is a 3h.p. unit.

Steve

[briansickler]

My ro requires a minimum of 20 psi inlet feed presure at all times or will shut down. The book states that the inlet pressure should not exceed 75 psi. So I think any pump that will maintain somewhere in the mid range would be good. Feed pumps for ro's don't generally have a pressure switch on them to come on and off like a water pump in your home. They run continuously all the time when the ro is running. This pressure, I believe adds to your total system pressure. You need to go by your ro capacity as to what size pump you need. What is your ro rated for flow? You could go on lapierre's web site and see what pump they are using for a similar size ro. Somewhere on there I was reading there spec sheets for all of their ro's....pump sizes were there.

Brian

[briansickler]

Look's like anything up to 250 g/hr unit has a 1/2 h.p. feed pump. So if you're at or below that, the pump will do just fine for you. Here's the spec sheet from Lapierre web site.

http://www.sugaringequipment.elapierre.com/down/gestion/groupeproduit/291/files/3.pdf

[TunbridgeDave]

Dan the Small Bro RO I have has the original Jacuzzi 7.8 amp 115v 1/3 hp feed pump with 1 1/4" inlet and 1" outlet. It stays above 60 psi with the system pressure at about 200 to 250 psi.