Does anyone have a pressure gauge I could borrow?

[jakano]

I have to buy a new RO/DI unit and I was wanting to get one of BFS's 150 gallon a day membranes but wasn't sure if I had enough water pressure or not. My pressure seems pretty high to me but I would hate to find out the hard way its not by wasting a ton of water with the membrane rejecting much more than it should be.

 

[hollback]

Just a side note Jason. I'd suggest going with a 75 gpd unit as those membranes are the most efficient. Is there a reason you're wanting a 150 gpd unit?

 

[jakano]

That's what I had before and it was just fine but Russ says the efficiency of the 150gpd is on par with the 75gpd membrane so why not go for more production. He rates both at 96-98 percent efficient with the proper pressure and temp. The 100 gpd is the real turd at only a 90 percent rating.

 

[MarineFishGuy]

From what Russ said when he came and spoke to the club, a booster pump is Required for the 150gpd membrane to get to 97%.
As I recall (been a while) it needs 85-90 psi to perform properly.
You are not likely to find this in any residential property.

At our house I get a max of 70 psi.
My old apartment was lucky to get 45 psi.
My previous house was around 50 psi.

When using a booster pump, you do not want to feed it from a saddle valve or the pump will burn out from being starved for water. The opening created by the needle is not large enough.

Personally I would run 2 separate RODI units with 75gpd membranes if I needed more water than I can produce. It would cost about the same (booster pump = cost of entire RODI unit) and give you some redundancy.

 

[jakano]

Well if that's the case then I'll stick with what I know works and get the 75gpd unit. I'll call him to be sure though since the ratings on his website say 60-90 psi for the 150. Maybe it's like you said and only truly that efficient at the highest pressure.

 

[jakano]

Well I spoke to Russ that day and he said the 150 can be ran at as little as 60 psi but that is bare minimum, and of course the higher the pressure the better it would work. But he said since I have a lot of starage capacity for water he would get the 75gpd unit and it would be fine. So thats what I did and it should be here today, and coulndt have been soon enough I ran out of water yesterday. Thanks guys for your input.

 

[hollback]

Nice choice Jason. Excellent customer service on Russ's end to direct you to a product that will suit your needs for less money. Very few vendors will do that.

 

[sammie]

If you need the volume, have you thought of doing tandem 75 gpd membrane housings? You would have the efficency with twice the output.

 

[jakano]

I'll look into that Sammie. I still have my older units ro membrane and housing maybe I can include it in the new system somehow. The old units cheap prefilter housings is what went bad on my eBay system, they all developed bad leaks one by one that I couldn't stop. Buying a new unit was only a little more expensive than replacing everything. The older membrane was still good so I'll try that dual setup and see how it goes. Do you know how I would hook it up to run two?