Issues with sand from well and short-cycling?

[Brian Keuer]

Hello all.
I am looking for advice regarding the following issue(s):
We moved into a new home about 1 and 1/2 years ago. We have an irrigation/sprinkler system that has had issues with sand/grit clogging the heads, etc. The irrigation company attempted to remedy this with a sand spin-down filter in garage to no avail. Of note, the RPZ valve is installed in basement just after the air-over-water well tank. Now the RPZ valve has been getting stuck with sand/sediment. The irrigation company thinks water treatments or well company needs to remedy this. I had well company look at issue and at end of last season they pulled up well pump about 20 feet thinking that would help the sand/sediment. Now it is clear this spring that is has not. Well company came out and notes that the well tank is waterlogged and has lost air charge (in less than 6 months). They think that this causes pump to cycle more frequently, pulling sand/sediment. They propose installing air compressor to keep air charge regularly, avoid service calls to charge well tank 2-3 times a year. This seems expensive and I am not confident there is not another solution. Well company is well-respected, and they drilled original well about 2 years ago.
Is there any other issues I should have them look at regarding the sand? Is installation of air compressor on top of well tank a reasonable solution with above issues?
Thanks in advance for any comments/feedback.

 

[Valveman]

If the well is for the irrigation only, just use a pump start relay from the irrigation controller to run the pump and it won't cycle. Or if the water is also used for the house, a CSV will keep the pump from cycling. Air over water tanks are bad about water logging. Why do you not have a diaphragm style tank? It would make life much easier. And yes when the pump is cycling on and off the well is being surged up and down, which can stir up the sand.

 

[Sponsor]

 

[Reach4]

We have an irrigation/sprinkler system that has had issues with sand/grit clogging the heads, etc. The irrigation company attempted to remedy this with a sand spin-down filter in garage to no avail.

You could add a 4.5 x 20 cartridge filter after the spin-down filter. Some cartridges are washable. 100 to 200 micron might be about right.

They propose installing air compressor to keep air charge regularly, avoid service calls to charge well tank 2-3 times a year. This seems expensive and I am not confident there is not another solution. Well company is well-respected, and they drilled original well about 2 years ago.
Is there any other issues I should have them look at regarding the sand? Is installation of air compressor on top of well tank a reasonable solution with above issues?

A compressor is very reasonable to automate the process. You could also do it yourself manually every couple months. Maybe a 2 cfm compressor, or maybe a classic big automotive tire pump if you are sufficiently motivated. Do not use a "250 psi" tire inflator.

 

[Valveman]

It doesn't matter how much air is in the tank. The pump will still cycle unless every sprinkler zone matches the output off the pump, or you have a pump start relay or a CSV. The more air in the tank, the less it will cycle, but it will still cycle.

 

[Brian Keuer]

If the well is for the irrigation only, just use a pump start relay from the irrigation controller to run the pump and it won't cycle. Or if the water is also used for the house, a CSV will keep the pump from cycling. Air over water tanks are bad about water logging. Why do you not have a diaphragm style tank? It would make life much easier. And yes when the pump is cycling on and off the well is being surged up and down, which can stir up the sand.

Thanks for your response. I really don't know why they did not install the diaphragm/bladder type tank. I believe they told me something about size of water service line, etc, etc...?
The well and tank are used for irrigation and the house-its a pretty massive tank, maybe 6 feet tall.

 

[Brian Keuer]

You could add a 4.5 x 20 cartridge filter after the spin-down filter. Some cartridges are washable. 100 to 200 micron might be about right.


A compressor is very reasonable to automate the process. You could also do it yourself manually every couple months. Maybe a 2 cfm compressor, or maybe a classic big automotive tire pump if you are sufficiently motivated. Do not use a "250 psi" tire inflator.

Thank for your response. If I did a cartridge filter, it would have to be right after the well tank, but before the RPZ valve (and the rest of our water treatment systems). The spin-down filter was installed after the RPZ valve, in between that and the irrigation heads. Now that the well company discovered that our tank is losing air so quickly and suspect short cycling, I am thinking that I should have that remedied anyways? I assume that the short cycling will eventually be hard on our pump, etc.

I am concerned because I am not aware of how or if well company investigated issue of air loss. Could there be a leak? A clogged pressure gauge? Something else?

Thanks again!

 

[Reach4]

The spin-down filter was installed after the RPZ valve, in between that and the irrigation heads.

Spindown to catch the biggest stuff, followed by the cartridge, is how I would think it would go. Both after the pressure tank.

 

[Valveman]

Air over water tanks lose the air charge as the air mixes and goes out with the water. You either need to just keep putting air in the tank somehow, or switch to a bladder/diaphragm style tank that doesn't lose air.