Grundfos SQ pumps should be stickied to the top of this catagory.


Chief Engineer, RedNeckTech Industries
Mar 1, 2020
Hello, a little late to the party here but this thread seems to be just what I was looking for. I'm looking at the 3 SQF-3 as a replacement for my conventional Gould but not 100% sure this is the right choice. Would love to hear some informed opinions.

My drilled well is 580 feet. Not sure of the static level, what's the best way to measure that? I have an 8K inverter with a 430 amp-hour battery bank. Looking to reduce my well pump's load so it doesn't draw down the battery bank too quickly.

No special water demands at house so I was thinking 2gpm would be fine (well yield is only 2 anyway).

Based on how deep my well is I figured the 3 SQF-3 was the right choice. Is that correct?

Figured I could just continue using the existing dedicated 240VAC/15A circuit for the Grundfos. Sound logical?

Please educate me...I'm all ears. Thank you.

One thing I would say is try to get a pump that outputs less than your well refresh rate. Pumping beyond the refresh rate creates negative pressure that tends to pull in more sediment and clog your well screen. I have a well that puts out about 2.5 GPM and so I have a pump that gives me a little less than 2 GPM. The level in the well never drops so I know I am not outstripping capacity. Of course at those flow rates you need a tank, I have a 2500 gallon so the slow fill rate is not a problem.


New Member
Sep 10, 2021
Speaking from experience I can say that in "general terms" the energy (KWH's) to pump a given amount of water will pretty much be the same. I'm sure the SQ if more efficient but not enough to warrant swapping out until the Gould fails. The main advantage of the SQ pump would be how much easier it is for your inverter to start but it sounds like you already able to run your Gould pump, right? IMHO, your money would be better spend on adding solar panels and/or expanding your battery bank. the load on my battery bank is going to be the same as my conventional Gould pump? You're saying the only difference is the soft start? Didn't realize that, I thought these pumps were more efficient. I'll go pack and check specs again.


Offgrid Cabineer, N.E. Ontario, Canada
Oct 29, 2019
Rural NE Ontario Canada
LOL... I have an SQ5, 260 deep, pushes to 50 Gal Pressure tank then another 75' to house.
Starting watts is 550W, stages up to 1100W by the time it reaches 52PSI cutoff
This is 120VAC as well, NOT 240VAC.

Softstart is certainly best for an inverter system and that applies to not only Water Pumps and quite a few electric motors can be retrofit with SoftStart modules.


Solar Enthusiast
Mar 27, 2021
I am in Florida and have a shallow well, we have an old fashioned hand pump to use in emergencies and it only takes a few pumps to draw water. The pump is 120v and is above ground. Can anyone suggest a soft start, energy efficient above ground shallow well pump motor?