Thanks for the further information. I did watch the video but wrote my reply wrong. Instead of cycle I should have said runs. Is the pump using a CSV setup running more then a large pressure tank setup (in my case tandem 119 gallons). Also is it advised to run a large pressure tank with a CSV or does that provide nothing of value?
Yes the CSV makes the pump run longer as it runs for as long as you are using any water, then for another minute to fill the pressure tank. Pumps are made to run 24/7/365. I have one that hasn't shut off in over 20 years so far. Running is what keeps the pump from cycling itself to death, which cycling is what a pump doesn't like to do. I can tell from you having two 119 gallon size tanks that you know how bad cycling is for a pump. But even with two 119 gallon tanks (60 gallons of water) the pump still cycles for every 60 gallons used. That is not much cycling compared to someone who doesn't understand how bad cycling is and only has a 44 gallon size tank (10 gallons of water). However it is still cycling and has all the other problems that go with cycling.
Yes you can use a Cycle Stop Valve with a large tank, even with two huge tanks like yours. As far as the number of cycles goes, the CSV with a large tank really is the best of both worlds. The two big tanks would give you 60 gallons to use for flushing, showering, etc., before the pump cycled even once. Then the CSV would keep the pump running constantly if you used more than 60 gallons or used water for long term, like running sprinklers for hours or days. But just like the number of cycles you get from having two big tanks should not be detrimental to the pump, the few cycles you will have with small demands using a CSV and a 4.5 gallon size tank would also not be detrimental to the pump. Then for long demands the CSV makes water go right past the tank, so it doesn't matter what size tank it is.
The money wasted on the two big tanks will provide nothing of value, and will cause big pressure fluctuation. With a 40/60 switch, two big tanks will cause the pressure to go down to 40 and be at the low side of the pressure delta for a long time. You could take a shower or two as the pressure dwindled down from 60 to 40 PSI. Using a CSV with two large tanks the constant pressure setting would be 59 PSI. So once the pump came on you would have strong constant 59 PSI for as long as you wanted to shower, even if that was a month. Only when you shut off the shower would the CSV let the tanks fill to 60 PSI in a minute or so and the pump would be shut off.
With a 4.5 gallon size tank (1 gallon of water) the pressure drops from 60 to 40 before you even know it, and the CSV holds a constant 50 PSI for as long as you are in the shower, even if the shower or sprinklers are on for a month. A constant 50 PSI in the shower will seem like so much stronger pressure than when the pump is cycling between 40 and 60 over and over, no matter the size of tank. 50 PSI constant also gives better sprinkler coverage than when the pressure is going up and down from 40 to 60 over and over.
I know it seems strange to go from two 119 gallon tanks to a little 4.5 gallon or 10 gallon size tank. But we have been doing this for nearly 30 years. Not only will you not hear any complaints, but hundreds of reviews will tell you how well it works here.
https://cyclestopvalves.com/pages/reviews
You can also see a video of a similar tank being replaced on this video.
