hef
New Member
Hello,
I need a new pressure tank for my cottage water system. (air pressure measured at bladder = 0)
Symptoms are good pressure at the cottage for a brief period of about 1 min, only to drop to very low until the pump cycles back on.
I have read about how to size a new tank but I want some other opinions as I know enough to be dangerous. It seems like a 20 gal total volumn would do the job, based on what I have read, but I am not sure.
I have a 1/2 HP J5SH Goulds pump which has a switch on point of 40 psi and a switch off point of around 60-70 psi. (This is what I set it to last spring which seems to produce brief, but decent pressure)
I have a toilet, bathroom sink, shower and kitchen sink and hot water heater.
Rule of thumb is only one of the above is on at one time.
The pump obtains its water from the lake - I estimate about a 5 ft lift from the water to the pump.
The pump pushes the water UP about 75 ft.
What is confusing to me is determing GPM for calculating tank size - if GPM varies with pressure as shown in the data below, how do you settle on a GPM for the pump?
From the Gould J5SH manual: (See attached as well)
AD3328 Venturi
AN019 Nozzle
Discharge Pressure – PSI
20 -- --30 -- -- 40 -- --50 ---60
Gallons per minute -------- -------- Max.Shut off
11.5 -- 11.3 -- 11.0 -- 7.7 -- 4.8 --------- 83
http://www.pumpsandwells.com/miva/JS+.pdf
Thanks for the assistance!
Regards,
Hef
I need a new pressure tank for my cottage water system. (air pressure measured at bladder = 0)
Symptoms are good pressure at the cottage for a brief period of about 1 min, only to drop to very low until the pump cycles back on.
I have read about how to size a new tank but I want some other opinions as I know enough to be dangerous. It seems like a 20 gal total volumn would do the job, based on what I have read, but I am not sure.
I have a 1/2 HP J5SH Goulds pump which has a switch on point of 40 psi and a switch off point of around 60-70 psi. (This is what I set it to last spring which seems to produce brief, but decent pressure)
I have a toilet, bathroom sink, shower and kitchen sink and hot water heater.
Rule of thumb is only one of the above is on at one time.
The pump obtains its water from the lake - I estimate about a 5 ft lift from the water to the pump.
The pump pushes the water UP about 75 ft.
What is confusing to me is determing GPM for calculating tank size - if GPM varies with pressure as shown in the data below, how do you settle on a GPM for the pump?
From the Gould J5SH manual: (See attached as well)
AD3328 Venturi
AN019 Nozzle
Discharge Pressure – PSI
20 -- --30 -- -- 40 -- --50 ---60
Gallons per minute -------- -------- Max.Shut off
11.5 -- 11.3 -- 11.0 -- 7.7 -- 4.8 --------- 83
http://www.pumpsandwells.com/miva/JS+.pdf
Thanks for the assistance!
Regards,
Hef
Last edited: