Hal_Ferguson78
New Member
Greetings Forum!
My Grundfos Model 3 SQF-2 pump (part of their SQFlex system with CU200 controller and provided PV panels) has failed and am considering replacing the pump with a 115vac single phase pump of 1/2 HP or less. I pulled the pump, know that the cable is good, and that the pump wouldn't start on 115 vac when placed in a large tub of water. I don't have first hand knowledge of what precisely failed, though the Sonoma County pump and drill outfit tells me that "the motor is fried." I'm hoping to avoid the cost of purchasing a new 3 SQF-2, prices for which have ranged from $4,400 from that pump outfit to $2,100 online.
We now have an off-grid PV-based system with what my numbers tell me is of adequate capacity to support a 115vac single phase pump of say 1/2 hp or so. I have 10,000 gal storage capacity so I don't need to pump a lot in a hurry -- if I can pump 3 GPM for 35 hours in a month's time, I can cover my highest monthly water use on record. I think I can do that during periods of full sun after the batteries have hit full charge, even after derating the PV panels due to age. As an aside, the cable from the tank float switch is bad; it shows the tanks full after it's been raining, so we've just told the CU200 that the tanks are not full by disconnecting the float switch input and manually turning the pump on and off at the CU200 periodically.
The questions are:
1) What pumps out there will run on my inverter-based 115vac, push a 330' head, be controlled from what amounts to an ON/OFF switch, survive being turned off regularly for a stretch of a week or two, have built-in dry run protection or shut off, and last more than 10 years?
I've looked at:
Sta-Rite HS Submersible Well Pump, S5P4HS05121
Gould 1/2hp 115v 2wire, 5G05412C
Franklin Tri-Seal 4400, 5JS05P4-2W115
I couldn't find a Grundfos 115vac solution.
2) Should I be bothering with any of this? That is, should I just suck it up and buy the dang Grundfos 3 SQF-2 and expect to do it again in 10 years?
Well Info
Casing: 5-inch ID PVC, blank to 120', perforated 120' to 260'
Static Water Depth: 120'
Estimated yield: 2 GPM
Pump depth (former): 230'
Water Storage
Two series connected 5,000 gal storage tanks approx 100' elevation above house and wellhead.
Power Source
Outback 24v system of 2 parallel strings of quantity 4 L16 batteries and quantity 8 210w PV panels with a VFX3524 Inverter / Charger producing 115vac capable of a peak 70A AC for 1 mSec and 50A AC for 100 mSec and continous AC RMS output of 29.2A AC or 3500VA. My existing system can not produce 230vac.
My Grundfos Model 3 SQF-2 pump (part of their SQFlex system with CU200 controller and provided PV panels) has failed and am considering replacing the pump with a 115vac single phase pump of 1/2 HP or less. I pulled the pump, know that the cable is good, and that the pump wouldn't start on 115 vac when placed in a large tub of water. I don't have first hand knowledge of what precisely failed, though the Sonoma County pump and drill outfit tells me that "the motor is fried." I'm hoping to avoid the cost of purchasing a new 3 SQF-2, prices for which have ranged from $4,400 from that pump outfit to $2,100 online.
We now have an off-grid PV-based system with what my numbers tell me is of adequate capacity to support a 115vac single phase pump of say 1/2 hp or so. I have 10,000 gal storage capacity so I don't need to pump a lot in a hurry -- if I can pump 3 GPM for 35 hours in a month's time, I can cover my highest monthly water use on record. I think I can do that during periods of full sun after the batteries have hit full charge, even after derating the PV panels due to age. As an aside, the cable from the tank float switch is bad; it shows the tanks full after it's been raining, so we've just told the CU200 that the tanks are not full by disconnecting the float switch input and manually turning the pump on and off at the CU200 periodically.
The questions are:
1) What pumps out there will run on my inverter-based 115vac, push a 330' head, be controlled from what amounts to an ON/OFF switch, survive being turned off regularly for a stretch of a week or two, have built-in dry run protection or shut off, and last more than 10 years?
I've looked at:
Sta-Rite HS Submersible Well Pump, S5P4HS05121
Gould 1/2hp 115v 2wire, 5G05412C
Franklin Tri-Seal 4400, 5JS05P4-2W115
I couldn't find a Grundfos 115vac solution.
2) Should I be bothering with any of this? That is, should I just suck it up and buy the dang Grundfos 3 SQF-2 and expect to do it again in 10 years?
Well Info
Casing: 5-inch ID PVC, blank to 120', perforated 120' to 260'
Static Water Depth: 120'
Estimated yield: 2 GPM
Pump depth (former): 230'
Water Storage
Two series connected 5,000 gal storage tanks approx 100' elevation above house and wellhead.
Power Source
Outback 24v system of 2 parallel strings of quantity 4 L16 batteries and quantity 8 210w PV panels with a VFX3524 Inverter / Charger producing 115vac capable of a peak 70A AC for 1 mSec and 50A AC for 100 mSec and continous AC RMS output of 29.2A AC or 3500VA. My existing system can not produce 230vac.
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