Advice on new well pump sizing

[Fireplug103]

I have a new well drilled to 440’ and my driller is telling me to set a pump at 420’. My water comes in at 330’ and the level of the water in the well is approximately at 70’. I’m getting approximately 4 gpm conservative as well. I will have another 30’ in elevation to the house where the pressure tank will be. I have a 1 1/2 hp 10 gpm pump currently in a shallower well that I would like to try to use or just get another pump for the new well and have both. I have been recommended a 1 1/2 hp 7 gpm pump for the new well. Any input would be appreciated for what size I should do and if what I have already would suffice. Thank you!

 

[Valveman]

You do not need a 7 GPM, in 1.5HP as it is made for a much deeper well. The 10 GPM, 1.5HP is made for a 400' deep well and will work fine, but to start out will only be lifting from 70'. It may even be larger than needed. Adding a Cycle Stop Valve will keep the pump from upthrusting when the water level is high, and make it work like a smaller pump when needed. I would use the 10 GPM, 1.5HP with a PK1ALT kit and a 20 gallon pressure tank.