Well pump problems

[CWL]

This ain't my first rodeo (so to speak) on water well systems, but I've hit a snag. I put in a new pump and pressure tank for my mom and dad a few weeks ago. When the pump comes up to pressure and shuts off it surges a couple of times like there is a water hammer issue or something. I have set the pressure in the air bladder on the pressure tank at 2 psi below the cut-in pressure on the pump. All the water lines have been ran to get any air out of the system. There is a ball valve between the pump and the pressure tank. I have tried shutting off the valve to check for any leaks internal to the system and both sides hold pressure. I also did a flow test to make sure the line between the pump and pressure tank was not restricted. The pressure tank is in the basement and the pump is outside about 40ft away. I thought about putting a check valve near the pump, but I think that the surge is too fast for a check valve to help. Would putting a water hammer arrester in line close to the pump help??? Any other ideas? I am concerned that the pump kicking off and on a couple of times at the end of each cycle will shorten the life of the motor and I know it's hard on the pressure switch. Also the pressure switch is new and came with the pump. It is a standard 30-50 switch.

 

[Dusty MI]

Sounds like you have two check valves. There should be only one. It should be between the pump and the well, bottom of drop pipe is best.

 

[CWL]

There is only one in the system right now. It is a foot valve on the bottom of the suction lines. I have checked it to verify that it is holding against pressure.

 

[OldFarmTractor]

Do you have enough air in the tank? It might have lost its charge.

 

[Anonymous-0]

Where do you have the pressure switch located at? Works best if located near the pressure tank.

 

[Anonymous-0]

My son had a similar problem. His outside line was quite long and was higher than his tank. It turned out that there was air trapped in the upper end of the water line and it would never come out of it. He had to undo the line at the highest point and manually fill it with water.

 

[Randy Losey]

I have seen this before during my plumbing service calls and as the one person mentioned, if your piping and pressure tank go downhill from your pitless adpt. there is usually a small bit of air trapped in the top highest portion of the piping.
Make sure from your pitless adpt. on your well casing that the 40 feet of piping has no sags or low spots and must go uphill with your tank being the highest elevation in the system. After the tank on the discharge side, it does not matter if you have low places or not. I also would remove the check valve you have between the foot valve and the tank. the foot valve is all you need and then a check valve on the discharge side of your pressure tank. Hope this helps.
Do you have a submerable pump or a jet style pump?

 

[Anonymous-0]

I've got one of those. All I did was remote mount the pressure switch with a needle valve in the line to adjust/dampen the surge so the switch doesn't cycle.

 

[Bob]

That's a GREAT solution.

I have worked with municipal systems that have a "surge timer"... a timer with a few seconds delay, so the pump can't start again, immediately, after the switch shuts it down. This allows any surge to settle down without the pump starting again. Using a "damper" restrictor needle valve on the pressure switch line should do about the same thing.

 

[CWL]

I could give that a try pretty easily. The pressure switch has a small flexible plastic line that connects to the pump housing. The pressure gage that I have mounted to the other side of the pump housing does a lot of bouncing while it's running from the pulse of the water being pumped.
Thanks

 

[Caseman 2]

Do you have a jet pump or a submerged pump, Does the pump kick back on,or are you just getting a surge?

 

[CWL]

It's a jet pump. When it reaches full pressure it will click on and off a couple of times real fast before it shuts off for good.

 

[Anonymous-0]

i think you have excessive pumping capacity . you need to throttle the water flow . try parshly closing the ball valve that is between the well and tank to slow the water flow until i quits bouncing. that maybe why that valve is there . its not normal to have a valve there except for throttling .

 

[Caseman 2]

Then you have air trapped somewhere, water won't compress and if you were completely void of air there wouldn't be any bounce. I would take another look at my pressure tank. Good luck

 

[Anonymous-0]

Your pressure switch should have an adjustment for differential, set this for a larger differential.

 

[Anonymous-0]

Is the water level less than 23 or 24 feet? With a jet pump, you need to throttle the water going to the tank so that a portion goes down one pipe to push the water up the other. sometimes if the water level is too high you can have this problem. If water is not lower than 24' use the pump as a shallow well. If deeper than that close the valve between pump and tank til surging ends.