Spot Free Production Rate seems low.

[Waxman]

Hi everyone

Just finished installing a new pump / motor for my Spot free water production.

Pur Clean 3000 gpd system.

Pump runs fine and produces ample reject flow but production rate feels slow. Production water is being made and holding tank is filling slowly. Production is less than half gal / minute ( on gauge) and reject is strong at 4 gpm.

Is this normal?

Might I need a new membrane?

Other problem?

TIA!

 

[soapy]

From what I have read about the best you can expect out of SFR system is 1 to 1 with most doing 1 part SF and 2 parts reject so your output of SFR seems low. To be a 3,000 gpd system it should put out 2 gallons per minute when the water temp is around 75 degrees. Low temp water reduces output rates. How long since you changed the membrane?

 

[Waxman]

I've never changed the membrane. I think it must be time.

 

[MEP001]

Was the production low before the new pump/motor?

What pressure are you running?

 

[Greg Pack]

Whats your membrane pressure? You can usually increase up close to the system's PSI rating until you get a better ratio.

Seems like I average about 1GPM out of a standard single 4x40 membrane.

 

[lag]

Pressure may just need to be higher, also as others asked what was it running before pump change?

I'm not familiar with your system, but does it have a "reject flow control valve" it may be wide open. Just a thought..

 

[Waxman]

I was running 50 psi +/_ on both pump and membrane pressure.

I adjusted reject and gate valves to increase to: PUMP: 101psi, Membrane: 110psi, Tap: 42 PSI. Max system psi= 180.

now testing to see how sfr product keeps up.

 

[MEP001]

Was 50 PSI before the new pump?

Does a portion of the reject cycle back to the pump?

 

[Waxman]

Was 50 PSI before the new pump?

Does a portion of the reject cycle back to the pump?

Not certain if I was at 50 psi before pump replaced. I do know it would not keep up with demand on peak days and reject rate seemed too fast compared to production.

I'm also not sure if a portion of reject cycles back through pump.

System is operating nicely now at about 100psi pump pressure. Reject is less and production is more.

 

[ready2go]

i have a d/h spot free rinse system and im finding i have no pressure at all.. and no manual .. any help? it is 58903-r.osystem

 

[Jsshac]

I was running 50 psi +/_ on both pump and membrane pressure.

I adjusted reject and gate valves to increase to: PUMP: 101psi, Membrane: 110psi, Tap: 42 PSI. Max system psi= 180.

now testing to see how sfr product keeps up.

Membrane and pump pressure are very low at 50 psi.