WATTS 0321987 VS CSV valve

Hi I picked up a WATTS 0321987 pressure regulator prior to finding this site. I'm trying to get better and more constant pressure from my well system. I have a goulds 1 hp J10S. I installed a Bosch tankless water heater without realizing the volume and pressure that it takes to work well. I'm wondering if the Watts Pressure regulator will be of much help. I'm running the pressure tank at 40 psi and the pump at around 42-62 however once the tank is depleted and the pump is running on it's own I experience a drop in pressure. Also the heater will kick in and out two or three times during a shower. Basically I want more pressure more consistently. Will the Watts valve help with this?

Thank you

I don't believe you need a PRV at all. A PRV prevents to water pressure from exceed the pressure you set it to. It has no way to increase pressure. City water pressure at times can be way too high for the valves in washers and toilets, and a PRV is the way to reduce that pressure. Your well system is set well below the pressure a PRV would normally be needed.

A PRV must be installed after the pressure tank and switch. With 42/62 pressure switch setting, you can set the PRV no higher than 42 PSI. After the pump comes on, this should give you a steady 42 PSI when using a small amount of water. The PRV will have 7 PSI pressure fall off as the flow rate increases to 10 GPM, so the pressure will drop to about 35 PSI. So your pressure will be fairly steady between 35 and 42, while the pump is cycling on and off continuously between 42 and 62.

A CSV looks similar but has a specialized by-pass that keeps the valve from closing to less than 1 GPM. So the CSV can be installed before the pressure tank and switch. Then the CSV could be set to 60 PSI. After the pump comes on, the CSV will hold the pressure fairly steady between 60 and 53, as the flow you are using changes from 1 GPM to 10 GPM. This will keep the heater working properly, and the pump will run continuously instead of cycling on and off.

Although, if the pressure is now dropping lower than 42 after the pump comes on, you have other problems. Either the pump is not pumping as much as it should, you have a suction leak letting in air, or the supply of water is not sufficient in the well. If the heater is kicking out 3 or 4 times during a shower, it makes me think that the pump is cycling between 42 and 62 while the shower is on. Which means you are not experiencing a pressure drop once the pump comes on, rather it just feels like the pressure is dropping because the pump is cycling on and off, which is common.

With a CSV installed before the pressure tank and switch, you can keep the pressure very close to the maximum setting, and the pump does not cycle on and off. With a PRV installed after the pressure tank and switch, the pressure will always be at the low end of the pressure range, and the pump will keep cycling on and off repeatedly.

If you dont have a under-performing pump, you could set 50-70+ psi at the tank and try the regulator at 45 psi at the house. Better test your pump first before that or a csv.