My Next Water problem

I excitedly opened my shiny new spectrapure RO/DI water filter. I read through the instructions on setting it up and run down with a smile on my face, hooked it up, and turned on the water.After dealing with a small leak, I had water being produced and was again elated with the new possibilities that awaited me. Then I checked my water pressure. It hovered at right 30psi! A tear rolled down my face, as I contemplated what I needed to do. A booster pump I realized was the solution - how much can one little booster pump be? Well, then I looked online at prices and you may have been able to hear my quiet sobs as the prospect of that much money needing to be spent...
So, I come to you now asking, is there anything that I can do to increase my water pressure without having to spend the $150 + on a booster pump (that I just plain do not have right now)?
My setup is as follows - I have a 1/4 tap from my main water line (sprinklers come off before I do, but that's it) that goes in 1/4 tubing to a shut off valve about 18 inches away. From that shutoff, another 18 inches (or so) of 1/4 inch tubing to the filter itself. Main water into the house has the valve completely open. The shutoff that I have in my line is completely open.

If I cannot increase pressure, what does this mean for the water that I get out of it? Does this diminish the life of the filter(s)? I honestly don't know the impact of this low pressure. All I know is the instructions say it needs to be a minimum of 40psi for the warranty and for optimum functionality.

Please help!

 

I am not sure on your questions. PM AZDesertRat with your questions. He is well versed in that area.

 

http://buckeyefieldsupply.com/showproducts.asp?Category=251&Sub=250

Heres one for $120, but yes, AZdesertRat will be your best bet, he'll set you straight

 

Not sure there is anything that can be done other than a booster pump.

Are you positive that every other water source in the house was turned off. I have noticed a huge PSI drop if even a toilet is running in the house, let alone a dishwasher.

 

Some newer homes have a pressure regulator on the incoming water line to lower pressure and act as a water saving device. You might check to makesure you do not have one. If you do, they are adjustable with a screwdriver or crescent wrench to adjust the diaphragm.

If you do not have a regulator, monitor your pressure and different times of the day. Often system demands are higher around supper time or later in the evening when people are bathing. You may find pressure are higher between say 8AM and 11 AM or in early afternoon when people are not doing laundry, dishes, watering the lawn etc.

40 psi is about the bare minimum pressure to get any kind of removal efficiency from a RO membrane, its also as low as Dow Filmtecs graphs and charts go. You membrane will not be as efficient and your DI will not last as long as a result of lower pressure.

Did you have the flow restrictor installed and adjusted to 4:1 waste ratio when you were seeing the 30 psi? If you had too much going to waste it would lower the pressure available to the membrane. An easy way to check this is slightly kink the waste line and see if the pressure goes up much, if it does you are probably wasting too much, it should not drop more than a few psi when set up properly.

I have 68 osi at the tap and still use a booster pump at between 95-100 psi to increase the rejection rate of my membrane and extend my DI life even further.

 

Thanks AZDesertRat for the advice (and everyone else as well). Couple quick questions about your response.
First, being that I'm in Colorado and we have been, and continue to be in single digit humidity and no moisture anywhere these days, I'm going through water quick in just keeping up with evaporation. I need water soon. Should I be able to use the little amount that this filter is putting out or is it not going to be good quality?
Second, I measured the waste and the good water as things stood for determining the flow constrictor adjustment and had 400 ml of waste to about 75 ml of good water. That ration came out to like 5.3 which was greater than the 4 to 1 ratio and less than the 6 to 1 so I had not planned on adjusting that - if anything I would have to get the restrictor replacement thing. I tried kinking the line as you suggested and only saw maybe an increase to 35 psi if that (probably more like 32 or 33). So does that seem like I need to get a different flow restrictor or something there?
I found on the web that for my city, the minimum psi is supposed to be 35. So, is it possible that with my 1/4 connections there just isn't enough flow to get that psi to my filter?

Thanks!

 

Sounds like 30-35 is going to be the best you get. What is your tap water TDS, your RO only TDS and your RO/DI TDS, this will determine if the water is good to use or not.

If your tap water TDS is say less than 100 you can trim your restrictor closer to a 3:1 waste ratio and pick up a couple psi since there will be less bypassing the membrane and going to waste. It will also increase your GPD and slightly decrease your RO only TDS.

The water is probably good to use since the DI will get what the membrane misses, it just will not last as long.

 

Whoo hoo! A plumber friend of mine checked into things (while at my place fixing a shower that I broke today) and fixed things up and I now have a psi of about 90-95! Must have been a clog or something in the line.
Thanks everyone for the advice and help!
One last question - which I didn't think I would be asking - is 90 or 95 psi too much? Sounds like that's what you run AZDesertRat, but wanted to make sure that was a good thing as it's in "the red" on the pressure guage.

 

Vendors say 80 psi but that is for liability purposes.
Membranes love pressure and work better the higher you go.
Most plumbing fittings and components are tested for a 125 psi working pressure, the only thing I migh tbe concerned with would be the pop off valve on your hot water heater as it may open due to the combination of pressure and expansion.

When you increase the pressure you not only gain GPD but the rejection rate improves extending the life of your DI resin dramatically.

 

I have 85-90 on my bulkreefsupply RO/DI, and no issues at all. The higher the pressure, the more flow you get ;D Obviously you would not want to throw 150PSI at it, but you should be good with that pressure. Just double/triple check for leaks!