Need help in determining gpm and psi at poc

zimmatic

LawnSite Senior Member
Location
Minnesota
I have a well contractor that has some troubles with a homeowner. The wrong pump was put in the well and now a new one needs to be installed. The homeowner wants to produce more water and the well can only give so much. So the well driller asked for my opinion on the matter and I have come here for some help.

Again, I am looking for the gpm and psi at point of connection in the house

The pump is at 147'(in the Hole) connected to 1.25" galvanized pipe. at 148' it converts to 1" poly and travels 75' into the house. Do not worry about well drawdown as that is not the issue (yet)

The pump is a franklin electric 35JS3S4-PE and the pump info is at http://search.franklin-electric.com...ystylesheet=11-AWS-Frontend&output=xml_no_dtd

The homeowner wants 35gpm at the poc and 60psi. I then will take a booster pump and push the water an additional 1300 to farthest head. I have to redo/gut the entire system.

The reason for a 3hp is due to the fact of existing wiring--go bigger and have to install new wires.

Thank you everyone
 

Wet_Boots

LawnSite Fanatic
Location
metro NYC
Nothing matters but the well itself - if it does not replenish at a rate of 35 gpm, then it won't supply 35 gpm - there is no way around that simple fact

Also, there will never be 35 gpm available to the house itself, what with the one-inch supply connection.
 
OP
Z

zimmatic

LawnSite Senior Member
Location
Minnesota
Dear Wet,

Thanks for the reply.
However, using the example given what would be the gpm and psi.

The well is rated for max gallons at 45gpm and that is pushing it hard or that is what is says on the well report for the county. I personally would say 35gpm is the max but the homeowner looks at what the county says.
 

Wet_Boots

LawnSite Fanatic
Location
metro NYC
Every well should have a performance log from when it was drilled. If you bet-the-ranch know it replenishes at 45 gpm, then you have no worries about a 35 gpm pump.

What was the previous pump? Why was it inadequate? How many acres are being watered?
 
OP
Z

zimmatic

LawnSite Senior Member
Location
Minnesota
The problem the well driller invoiced the homeowner in 04 that 35gpm will be at the house poc and it is only at 22. The homeowner started irrigating approx 1/2 acre and now is watering 3.5 acres. I am the 3rd irrigation company he has gone through and now he trust me since I fixed the cycling problem of the current well by installing a f/w pump before I guess they had went through 4 booster pumps before I showed up. Lots of work renozzling and consolidating zones to keep well from cycling.

IMO I wont be the ranch on 45gpm.


The previous/ current pump is roughly 19-22 gpm at 60psi in the house or that is what I have calculated by the performance of the irrigation.
I do not have the current model #of the pump.
 

Wet_Boots

LawnSite Fanatic
Location
metro NYC
You need to find some replenishment rate you can trust your reputation to. Is it at least 35 gpm? If there is no trustworthy performance log, then you can only try the larger pump and see what happens.

Where is the well, relative to the house? Any obstacles between them? (like anything that won't allow a new supply line installed)
 
OP
Z

zimmatic

LawnSite Senior Member
Location
Minnesota
Sorry guys for asking for help on this. I hate when a person askes for info to only find out thier real movties. I talked to the well driller. and now he is going to draw up a proposal to have a larger pump 45gpm isntalled with a 2" line and larger wires going to the house in a new trench etc. Its like if you want me to confirm you doubts heck yeah your not going to get 35gpm at the house even if you raise the pump to 120'


thanks guys for your help and info.
zim
 

Wet_Boots

LawnSite Fanatic
Location
metro NYC
We don't know the water level in the well, do we? Obviously it has to be higher than the pump. I expect mid-high twenties for a well as described, with the proviso that the drop pipe and supply line is replaced with 1-1/2 inch minimum.
 

Top