Replaced submersible pump and pressure tank. No water pressure now

[Dinah McCoy]

We just replaced our 1 and half horse submersible with new pump the same horse power. Ended up also replacing the pressure tank (30-50)and all the fittings, pressure switch, and gauge above ground. Old system was about 20 yrs old from what we were told and had lots of corrosion on the above ground pipe. Did not replace pipe from ground level to pump (385FT pvc?). The new system will not build pressure above 20 psi and loses down to 0 when any faucet is turned on. Tank air pressure is 28. System will hold pressure from check valve on. Not sure on any of the specifics of the well itself. Bought the home 5 yrs ago and have never had a well before this, so still learning about them! This is the first problem we have had from it.

 

[Reach4]

We just replaced our 1 and half horse submersible with new pump the same horse power. Ended up also replacing the pressure tank (30-50)and all the fittings, pressure switch, and gauge above ground. Old system was about 20 yrs old from what we were told and had lots of corrosion on the above ground pipe. Did not replace pipe from ground level to pump (385FT pvc?). The new system will not build pressure above 20 psi and loses down to 0 when any faucet is turned on. Tank air pressure is 28. System will hold pressure from check valve on. Not sure on any of the specifics of the well itself. Bought the home 5 yrs ago and have never had a well before this, so still learning about them! This is the first problem we have had from it.

Not all 1.5 HP submersible pumps are at similar.
An 18 gpm 1-1/2 HP pump would behave similarly to what you describe.

A 25 gpm 1-1/2HP pump would not even pump water from 300 ft. It could be compared to trying to climb Pike's Peak on a 10 speed bike in high gear (imperfect analogy).

A 7 gpm 1-1/2 HP would provide more pressure than you need with plenty of flow. A 7 gpm 1 hp pump would provide plenty of water for a house.

A 1-1/2 HP 10 gpm would provide enough.

 

[Sponsor]

 

[Dinah McCoy]

Not all 1.5 HP submersible pumps are at similar.
An 18 gpm 1-1/2 HP pump would behave similarly to what you describe. A 25 gpm 1-1/2HP pump would not even pump water from 300 ft. It could be compared to trying to climb Pike's Peak on a 10 speed bike in high gear (imperfect analogy).

A 7 gpm 1-1/2 HP would provide more pressure than you need with plenty of flow. A 7 gpm 1 hp pump would provide plenty of water for a house.

A 1-1/2 HP 10 gpm would provide enough.

 

[Dinah McCoy]

Like I said still learning! Did not know this, we were told count your faucets...that is the gpm you need.nothing about well depth. So more specifically it is 1.5 hp 18 gpm pump. Not correct one. Need lower gpm deeper you go? So back to square one, another new pump. Is this chart universal or do all the pumps have them?

 

[Reach4]

Like I said still learning! Did not know this, we were told count your faucets...that is the gpm you need.nothing about well depth. So more specifically it is 1.5 hp 18 gpm pump. Not correct one. Need lower gpm deeper you go? So back to square one, another new pump. Is this chart universal or do all the pumps have them?

All pumps have graphs, and most have tables similar to what I showed, which are easier than graphs for the less experienced.

The numbers on the graphs will vary from brand to brand, but will usually be similar.

7 gpm is enough for most houses. 10 gpm is enough for large houses. Major irrigation is different, but for yard watering, you size the irrigation nozzles and zones to the pump, rather than the pump to the nozzles. A 10 gpm pump will often pump pump more than 10 gpm, depending how deep the surface of the water is. Based on your experience with the 18 gpm pump, you know your water is fairly deep. A 7 gpm pump will generally cost more than a 10 gpm pump; it has more stages. One thing to consider is if you have a backwashing iron filter, that might take 10 gpm or more depending on size and media. Softeners generally take 2.4 to 5 gpm to backwash, depending on size.

The deeper the water is, you need more stages which give more pressure, but usually less gpm rating for a given HP. Your wire is probably sized for 1.5 hp, so you would probably not want to go to a 2+ hp pump. So as I see it, a 1.5 hp 10 gpm pump would be a good fit.

 

[Dinah McCoy]

No softeners only a sediment filter located at the house. Not looking forward to re pulling that pipe. The original did not have the flange thing or a safety rope on it. We did add the rope but not the flange while we have it up again should we put one on. Thank you for your help!

 

[Bannerman]

You mention the system holds pressure from the check valve forward, which implies there is a check valve after the well, likely just before the pressure tank. As there will be a check valve within the pump, there should be no additional check valves installed after the pump as they often cause water hammer and other issues. Once the additional check valve is removed, the pressure tank will keep the entire system pressurized including the drop pipe leading back to the pump.

As your system is equipped with a 30/50 psi pressure switch, because the system pressure cannot build to above 20 psi, the pressure switch will not shut off the pump so the pump will be deadheaded for as long as power continues to be supplied. Because a deadhead condition results in 0 water flow, there will be insufficient flow across the pump motor to cool it so the pump motor is likely to overheat and will likely shutoff if there is a built in thermal protection switch. When no thermal protection is built in, the water in the well can become hot enough to boil. With either situation, the motor can soon fail due heat buildup.

 

[Reach4]

A 7 gpm 1 hp would also seem to be a good choice. If your water stays deep, a 7 gpm 1-1/2 HP could be a good choice. You might then adjust your pressure switch to 40/60 psi if you would like a little more pressure.

 

[Dinah McCoy]

We have the breakers to well turned off since the pressure would not build to the point of shut off. The original system had a check valve also we just mimicked the original on all parts.

 

[Valveman]

We have the breakers to well turned off since the pressure would not build to the point of shut off. The original system had a check valve also we just mimicked the original on all parts.

Having that check valve there was wrong and probably causing problems all along. You don't have to change the motor. Just get a 10 GPM liquid end made to put on the 1.5HP motor you have.

 

[Dinah McCoy]

Having that check valve there was wrong and probably causing problems all along. You don't have to change the motor. Just get a 10 GPM liquid end made to put on the 1.5HP motor you have.

Having that check valve there was wrong and probably causing problems all along. You don't have to change the motor. Just get a 10 GPM liquid end made to put on the 1.5HP motor you have.

Got it.. replumb that section and remove valve.

 

[Bannerman]

Recommended to not use a safety rope or torque arrestor. If the rope is ever dropped into the well, it is likely to become balled-up above the pump, often making it impossible to remove the pump. A torque arrestor is an additional device that can also lead to the pump becoming jammed in the well casing while attempting to remove it.