Reverse Osmosis pressure

I just bought a Spectrapure 180gpd reverse osmosis unit. I am having trouble with the water pressure and I am trying to find ways to get the pressure up before spending $$$ on a pump.

My gauge is reading 38psi. My unit is hooked up to my bathroom sink faucet via a hose adapter. Will I get more pressure if I trim off a couple feet of the black supply tube? Will I get more pressure if I hook up the unit underneath the sink and bypass the sink fixture? I am sure you lose some PSI through hoses, and tubes but enough to make a difference?

 

Actually you shouldn't see much loss or pressure through the 1/4" tubing. Sounds like you have poor pressure at your house. I have my supply tubing at least 15' from the source and I see 85 PSI. You may need a booster pump unfortunately.

 

Thanks Marshal, I'm going to see if I can increase the pressure at the main valve tomorrow. If not, looks like another $125 gone.

 

$125 for the system, or for a booster pump?

 

Man these Spectrapure pumps are expensive! Anyway, 38PSI is just plain abysmal, and I doubt it can be effectively increased. Even if you were to squeeze out a phenomenal 10PSI increase (which you won't by the way), 48PSI is still ridiculously low.
You NEED a pump, period.

 

$125 for the booster pump. Although I did call Spectrapure today and talked to a rep and he said not to buy a pump If I am not looking to produce alot of water per day. I will only be making 10-15 gallons per week. He said my membrane will last without problem 2-4 years if I change the other filters out when I notice a pressure decrease or every 6 months, whichever comes first. I have the 180gpd unit and it took me about 8 hours to fill up 50 gallons for my intitial tank filling. So plenty fast enough for me. I am just worried about dumping $80 into membranes in 6 months because my pressure is too low.

 

I have never looked into booster pumps for RO systems, but maybe there is a less expensive one out there? I would still consider it either way. Pressure is the most important factor in a properly running RO system.

 

The dual membrane 180 requires 65 psi to function properly. This is well advertised and unfortunately you should have checked your pressure before purchasing a RO/DI system of any type. This is a required piece of information you should have along with water temperature and general water conditions so you can size the unit properly and get the correct cartridges.

Spectrapure uses only Aquatec booster pumps and they are the best you can buy anywhere so are not cheap but really $139 for the complete kit including the upgraded larger power supply, pressure switch and all the fittings is not bad:
Booster Pump Kit for SpectraPure 60, 90, & 180gpd Manual-Flush Systems

Yopu might try buying a hose bib pressure gauge kit at Lowes or HD for less than $10 and check your outside pressure. If you home is newer you may have a pressure regulator on the incoming line per your local building codes to reduce pressure, they are usually adjustable with a screwdriver or crescent wrench if you do. I would try to get it close to 65-80 psi if at all possible. Its not your membranes you will be exhausting but the DI cartridges since the membranes rejection rate or removal efficiency will suffer at lower pressures. The sediment and carbon filters are keeping the membrane clean and the waste ratio will keep it flushed but it will no tbe efficient at lower than 65 psi so DI suffers.

 

I was hoping to get a response from you, thank you!
Yes, I should have checked my pressure before ordering but really it wouldn't have changed anything. I still would be in the same boat of needing a booster pump as they all seem to need about 60psi or higher for best production. Although this RO/DI unit is advertised as needing 40psi to 80 psi not 65 psi, it also reads this way in the manual.
I checked my pressure on the outside hose bibs and they are also at 41psi. And I also tried adjusting the pressure regulator and it wasn't able to increase the pressure anymore (only decrease it).
Thanks again for all the good advice and the link for the booster pump, I might just go ahead and order it.

 

Not really in the same boat.
Most any single membrane system should still operate at 96+/- % rejection rate at 40 psi unlike a dual membrane system which requires a minimum of 65 psi to be efficient.

You could, for now anyway, remove one membrane and place it in a seal a meal type bag with some water in it so it stays fresh and place it in the back of your refrigerator. Replumb the system with a single membrane and change the flow restrictor to match the single membrane and only have about $5-$6 invested plus have the option to reinstall the second membrane in the future, keep it as a spare or sell it to someone who needs a good membrane.

The 40-80 is their standard answer for single membrane systems but Spectrapure has always published 65 psi as their recommended minimum pressure for a dual membrane system , they will function at 60 psi but not as efficient. I owned one myself for many years before switching to their UHE-100 system and I was lucky enough to have 68 psi at the tap.