Filling a swimming pool (pump cycling)

[Rxdad2012]

Bought a house about a year ago, in the breaker box was a breaker labeled pond pump. We have a man-made pond on our property fed by a spring stream. Got everything out and checked it out. Not sure what HP the pump is but it looks like a small submersible pump. The previous owner had a pressure tank installed as well. (Keep in mind this is about 300 feet away from my house--we have 6 acres total). Turned the system on and discovered the pressure tank was rusty and had several leaks. Not sure how many gal it was, but looks to be 36 or so. Replaced it with a new, 20 gal tank. Checked the air pressure in the tank and set it at 18psi since my switch is 20/40 (Kept the same pressure switch, which is 20/40). The water from the system is pumped to a spigot about 300 feet up a pretty steep hill. With the system on, it's outputting 10gpm, which seems pretty good to me. All of that to get to my question (sorry): with the spigot fully open, the pump cycles off and on in about 16.5 sec intervals, so it pumps for 16 sec, off for 16 sec. I know this is bad for the pump's life! I've watched the pressure on the tank with my gauge as it cycles back and forth and the pump cuts in at 30psi and cuts out at well over 60psi. Do i need a different switch or a bigger pressure tank? I'm thinking about returning the 20 and upgrading to a 36. I'm new to well systems and I'm trying to learn as much as I can but I would appreciate any insight you guys have as I may use this source as a backup water source to my well that I use in the home. Thanks so much!

 

[LLigetfa]

If you increase the cutout PSI, the pump will most likely move up the curve to match the GPM draw. Just make sure it can and does still shut off when you close the valve.

 

[Sponsor]

 

[Rxdad2012]

If you increase the cutout PSI, the pump will most likely move up the curve to match the GPM draw. Just make sure it can and does still shut off when you close the valve.

Thanks! I'm not sure if the switch is single post or double post but i will look. On a single post, the larger nut turned clockwise increases the cut out psi, right?

As far as checking the air pressure in the tank, I've seen several different opinions. I usually shut the power off and leave that spigot open until water stops coming out. Is that correct?

 

[Reach4]

Thanks! I'm not sure if the switch is single post or double post but i will look. On a single post, the larger nut turned clockwise increases the cut out psi, right?

On most pressure switches, the nuts are the same size. The nut on the bigger spring clockwise will raise both the cut-in and cut-out, which is what you want to do.

As far as checking the air pressure in the tank, I've seen several different opinions. I usually shut the power off and leave that spigot open until water stops coming out. Is that correct?

Yes. If you raise the precharge first, you will avoid over-stretching the diaphragm.

 

[Valveman]

With the 36 gallon tank the pump will cycle about every 25 seconds instead of every 16 seconds as with the 20 gallon tank. The only way to keep the pump from cycling is to use a large enough valve and hose, so the pump cannot produce more than you are using. Or you could use a Cycle Stop Valve and water anyway you want. If you put a CSV on this well you will probably want it to be the primary well for the house, because it will be delivering constant pressure, which is much stronger shower pressure than when the pump is cycling.

 

[Rxdad2012]

With the 36 gallon tank the pump will cycle about every 25 seconds instead of every 16 seconds as with the 20 gallon tank. The only way to keep the pump from cycling is to use a large enough valve and hose, so the pump cannot produce more than you are using. Or you could use a Cycle Stop Valve and water anyway you want. If you put a CSV on this well you will probably want it to be the primary well for the house, because it will be delivering constant pressure, which is much stronge shower pressure than when the pump is cycling.

Good stuff. Thanks for the comments thus far, everybody!