2 and 1/2 pressure tanks precharge

[emstone]

Hey everyone, I'm trying to troubleshoot some water hammer issues in my plumbing system. It's a large property with a few buildings, and I have a solar piston pump with a small pressure tank on top (kind of like a expansion tank) that seems to be causing a lot of noise and vibration in the pipes. I suspect this is contributing to pinhole leaks in some of the copper lines.
Originally, the system had a steel pressure tank immediately after the pump, but I think it's no longer functioning and they added one at other end of the system that was easier for them but does nothing for my water hammer. I'm planning to replace it to help absorb the shock from the pump and leave the other one in place.

My question is: how should I set the pressure in each of these tanks: the 1.2 gallon on the pump, the 32 gallon at the pump and the 32 gallon on the other side of the system. Will they all be the same, or should they be different? Any advice from experienced plumbers would be greatly appreciated!

I plan to have the plumber take care of this, but they don't always seem to be really knowledgeable and the drilling company that normally handles this stuff is just too busy to help me anymore with inside the house stuff.

Thanks I'm advance!

 

[Valveman]

When do you experience water hammer? Pump start, pump stop, valves opened or closed, etc,?

 

[Sponsor]

 

[emstone]

When do you experience water hammer? Pump start, pump stop, valves opened or closed, etc,

This is a dankoff solar force pump. While operating the pump goes kacha kacha kacha with every piston push. All the faucets in the general vicinity are receiving that high velocity waves each time the piston drops pushes. So it's not technically a valve nor is it a problem with the pump going on, It's just a problem with the pump operating as a piston. The plumbing closer to the operating pressure tank does not seem to have this problem, although it's also the furthest plumbing so it could just be the amount of water in the system.

 

[Fitter30]

Can you vary the starting ramp verses filling ramp filling has to to longer than starting.

 

[Valveman]

This is a dankoff solar force pump. While operating the pump goes kacha kacha kacha with every piston push. All the faucets in the general vicinity are receiving that high velocity waves each time the piston drops pushes. So it's not technically a valve nor is it a problem with the pump going on, It's just a problem with the pump operating as a piston. The plumbing closer to the operating pressure tank does not seem to have this problem, although it's also the furthest plumbing so it could just be the amount of water in the system.

That is not really water hammer, but pulsation from the piston pump. We use accumulator tanks on the discharge of our stroker pumps on the drilling rigs. The "steel tank" you had before was acting like an accumulator tank. Bladder or diaphragm tanks don't make as good accumulators as a standard tank. But maintaining the air charge in a standard tank is a never ending job. I think you can use a diaphragm tank. But it will need to have larger than 1" opening and be placed correctly to absorb the pulsing. I would come off the pump with an 1 1/4" tee. One side of the tee would be connected to a 44 gallon size or larger diaphragm tank (needed to have the 1 1/4" inlet), the other side of the tee is necked down to 1" and sends water to the house. The idea being that the 1 1/4" tee and tank opening can absorb the pulses and not send any down the smaller 1" line.

Piston pumps work ok with solar because they will pump at any RPM. Centrifugal pumps need a certain RPM to produce the pressure needed, but do not pulse like a piston pump, which is why centrifugal pumps are use the majority of the time.

 

[Fitter30]

Look at piping page 25. Have surge tank and a.spring check?

https://dankoffsolarpumps.com/wp-content/uploads/DANKOFF-SOLAR-SolarForce-Installation-Manual-1.pdf