Greensand System Installed... Low Pressure?

[rjh2o]

Well pump output yes. It should be on the pressure tank, well pump control and/or with the paperwork you got with the well installation. You are only going to get 5-7 gpm with this system. If you have a well that is producing low output (gpm) the gpm through greensand system will be even less. As Gary stated the sfr through the "valve" alone may be 18gpm but not the the media tank with 1.5 cu ft of greensand.
RJ

[Akpsdvan]

Just double check any number of the books that I have for the Greensand units with a 10x54 or 1.5 cubic foot and they all have 5.0gpm on the backwash...

They also have a max service flow rate through the greensand at 5gpm.... for the same 1.5 cubic ..

[mialynette2003]

You should be backwashing a 1.5 cuft greensand filter at a higher gpm than his 5 gpm.

according to the manuals I have the max backwash flow rate for a 1.5 cf Greensand is 5.0 GPM.

[rjh2o]

I would agree with Gary. The dealer quoted you the flow rate through the valve alone. The max flow through the 1.5 greensand will be 7gpm. Just a bad application for any modern home. That unit requires 10gpm backwash flow rate. Yes I meant the output of the well.
RJ

[Gary Slusser]

according to the manuals I have the max backwash flow rate for a 1.5 cf Greensand is 5.0 GPM.

The backwash gpm is a drain line flow control (DLFC) that can be changed and usually most control valves can go to 10 gpm and if you need more you remove the DLFC from the control valve and add an inline flow control in the drain line itself.

RJ, then I assume you mean the output of the well pump and not the recovery rate of the well.

[mialynette2003]

I would agree with Gary. The dealer quoted you the flow rate through the valve alone. The max flow through the 1.5 greensand will be 7gpm. Just a bad application for any modern home. That unit requires 10gpm backwash flow rate. Yes I meant the output of the well.
RJ

Everwhere I've looked shows 5 GPM backwash flow rate for a 1.5 cfr greensand. Where do you find info that says 10 GPM? Just for my knowledge.

[Gary Slusser]

Look up the spec sheet on greensand per cuft and I'm pretty sure you'll see higher th n5 gpm for a 1.5cuft greensand filter.

Also, there are two of us, maybe three, that says more is needed if the filter is going to operate as it should over time, than the 5 gpm the seller is calling for. That's based on actual experience troubling shooting the stuff over many years. Personally I wouldn't sell greensand (Pyrolox too) filters and didn't since like 1992 or so.

Plus the fact that the constant SFR of the 1.5cuft filter seems to be too low for the household's peak demand flow rate.

[mialynette2003]

I agree that a 1.5 cf greensand needs more backwash flow rate, but when a unit is ordered, it will come with a 5 GPM DLFC. So are we to second guess the factory and replace it with a larger one? If so, what size? Would it void the warranty because of an unauthorized change?