Two pressure tanks in series

[Gkallio]

There have been related threads to this one but replies seem to be mixed so I'm posting this. My well & submersible pump system has two pressure tanks. One is a small 2-gal unit with a pressure switch located in the well pit along with the pump control box. The second one is a 44-gal unit in the house crawl space without any pressure switch. The main water line between well and crawl space is about 100' long, 1-1/4" diameter I believe. There is a check valve just before the tee to the 44-gal tank. My question is whether I need to have an additional pressure switch at the 44-gal tank? Or, should I remove the pressure switch at the 2-gal tank and put it next to the 44-gal tank? (Both options would require some additional wiring that I'd rather not have to do.) I know there will be some pressure drop in the 100' line that some folks have claimed will cause the well pump to cycle on-off again briefly after filling the 2-gal tank. BTW, I do not know why there is such a small pressure tank in the well pit - maybe because that was the largest size that could fit and the 44-gal was added later to reduce cycling? I also know there used to be an AquaGenie flow controller in this system but it has been removed - but not sure if this is relevant. Thanks for any help!

 

[LLigetfa]

I think the AquaGenie was the precursor to the CycleStopValve which stops short cycling as the name implies. I further suspect that the 44 gal tank was added after the AquaGenie was removed.

 

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[Gkallio]

Yes, that is probably true. My parents built the house for retirement in 1977-78. They have passed and I'm now trying to reconstruct the history of this 45 yr-old water system. I have an itemized receipt for the original well pump installation (Oct 1976) and it includes the AquaGenie and a check valve, but no pressure tank. I have a receipt for the 2-gal Well-X-Trol pressure tank installation (Dec 1997) with a note "to replace AquaGenie". I also have a receipt for a 20-gal Flexcon pressure tank (Oct 2006) which was installed in the house crawl space without a pressure switch. The house is currently being remodeled and the 20-gal tank was found to have bladder leak (water in air chamber). So, I just replaced it with a new WaterWorker 44-gal tank but the system has not been turned back on yet. The plumbers think it needs its own pressure switch but they are not well specialists. Having a pressure switch for each tank doesn't make any sense to me since they will never be exactly synchronized and will compete with each other. So, I'm thinking the system is fine with just the one pressure switch at the 2-gal tank since it has been working that way for many years. But I'd really like to hear from a well specialist to confirm!

 

[LLigetfa]

The plumber is right in so far as needing a pressure switch at the 44 gallon tank but I have doubts they proposed keeping the switch at the pump. Depending on how many GPM the pump can produce will determine how badly it might short cycle while the 44 gallon tank fills. Also, where the sense line connects can affect the outcome.

 

[Valveman]

The pressure switch needs to ne close to a pressure tank. Many times people will put a small tank close to the well with the small pressure tank attached. Adding another tank further down the line can be a problem as they don't fill at the same time.

You need to replace the Aqua Genie with a Cycle Stop Valve, then the tank size is almost moot. The Aqua Genie was a first attempt to make a constant pressure valve like the Cycle Stop Valve. Even with its flaws the Aqua Genie made pumps last 30-40 years even with a small pressure tank. Eliminating the pump cycles with an Aqua Genie or Cycle Stop Valve makes pumps last so long that the company who owns Aqua Genie stopped making them because it was cutting into their replacement pump business.

You can't add enough tanks to make the system work as well as it does with a Cycle Stop Valve. The CSV will make the pump last even longer than the Aqua Genie did, and will deliver strong constant pressure to the house and shower.

 

[Lschuerch]

I have a shallow well pump with a pressure tank on it, which also has the pressure switch,
these are located out in the pump house along with the filters and UV light.
I would like to move the filters, and uv light to a basement where it can be heated. I would like to install a 20 gal pressure tank in the same location in the basement. My question is can I put the tank in and rely on the pressure switch out at the pumphouse to shut the pump off when the system reaches pressure? To insulate and heat the pumphouse would require a lot more work.
The well is 30' deep and the pump is 3/4 horse. It is approx 50' from the pump house to where I want to install the pressure tank. It is all downhill.

 

[Valveman]

I have a shallow well pump with a pressure tank on it, which also has the pressure switch,
these are located out in the pump house along with the filters and UV light.
I would like to move the filters, and uv light to a basement where it can be heated. I would like to install a 20 gal pressure tank in the same location in the basement. My question is can I put the tank in and rely on the pressure switch out at the pumphouse to shut the pump off when the system reaches pressure? To insulate and heat the pumphouse would require a lot more work.
The well is 30' deep and the pump is 3/4 horse. It is approx 50' from the pump house to where I want to install the pressure tank. It is all downhill.

You will need to move the pressure switch as it must stay with the tank. Even if you move the tank to the house the pump will need to be protected from freezing. You could use a PK1A kit with a little 4.5 gallon size tank. It would work better than a 20 gallon size tank and you might be able to insulate and heat the pump area when using such a small tank.