Don't understand what my pressure tank gauge is telling me. I have a Cycle Stop Valve.

[JEG in Raleigh]

Please see the attached photos. I have a 44-gallon pressure tank and a Cycle Stop Valve on my system. I am not having any problems with my water pressure or well pump, but something has changed since I first installed my current pressure switch, gauges, and Cycle Stop Valve a couple of years ago. My pressure switch is a 60/40 switch and I did not change the factory setting of the switch. I just checked the tank pressure at the Schrader valve on my pressure tank and it reads 55 psi. In the photos, you can see the pressure when the pressure switch activates and turns on and it is 20 psi. Another photo shows the pressure when the pressure tank has filled and the pressure switch has turned off the pump and it reads 40 psi. The pressure on the 2nd pressure gauge that I have installed immediately in front of the Cycle Stop Valve (between the well pump and CSV) reads 60 psi once the pressure tank has filled and the pump has shut off.

If a pressure switch shuts off the pump at 60 psi and all valves in the house are closed and the check valve at the pump is not leaking, then the system pressure throughout all the pipes in the house, in the pressure tank, and back down the well to the check valve would all be 60 psi, and that would explain the pressure gauge by the Cycle Stop Valve reading 60 psi, is that correct? If that is correct, then why is the pressure gauge at the pressure tank reading 20 psi at the point that the 60/40 switch turns on and 40 psi when that switch turns off? Does that indicate a bad gauge or is something else going on that I don't understand going on? Please explain. Thanks!

 

[Valveman]

When the pump is off, the gauge before and after the CSV should read the same, as well as the air pressure in the tank. Your tire gauge is probably 5 PSI off from the water pressure gauge, which is normal and why it reads 55 when the other reads 60 PSI. I assume the gauge before the CSV is still fairly accurate, as a 40/60 pressure switch is usually dependable at 40 to 60. Those liquid filled gauges have a tiny hole for the water to go through, which is what makes them not flicker like a cheap gauge. But the tiny hole has a tendency of clogging up. You maybe able to fix the gauge by just using a small pin to unclog the hole. Cheap gauges flicker but are better as they don't have that small hole and the flicking is needed to see what is really happening in the system.

Looks like a 5 dollar pressure gauge is your only problem. Pressure gauges have nothing to do with how the pump system works. Gauges are only there for you to see what is going on. You really don't even need a gauge. If the pressure switch is clicking on and off when needed you can be fairly sure it is at 40/60. If the pump never shuts off while a shower is running, you can be sure the CSV is working properly. If after shutting off all taps, if it takes a minute or two before the pump shuts off, you can rest assured everything is still working fine without every looking at a gauge.

With the CSV in control you are not likely to have any pump system problems for decades to come. You will go through a lot of pressure gauges during the life of the CSV and pump system it controls. You may even want to put 1/4" ball valves before each gauge. That way you can shut the water off to the gauge unless you want to see it, which will make them last much longer.

 

[RS]

Like what Valveman said, gauges don't agree that close! What I do when setting up a system is to shut off the power to the pump, then slowly bleed off the pressure while watching the gauge. When the pressure switch clicks to start the pump, the gauge should slowly drop about another 2 psi, and then quickly drop to zero. that confirms that the preload in the tank is correct.

 

[JEG in Raleigh]

When the pump is off, the gauge before and after the CSV should read the same, as well as the air pressure in the tank. Your tire gauge is probably 5 PSI off from the water pressure gauge, which is normal and why it reads 55 when the other reads 60 PSI. I assume the gauge before the CSV is still fairly accurate, as a 40/60 pressure switch is usually dependable at 40 to 60. Those liquid filled gauges have a tiny hole for the water to go through, which is what makes them not flicker like a cheap gauge. But the tiny hole has a tendency of clogging up. You maybe able to fix the gauge by just using a small pin to unclog the hole. Cheap gauges flicker but are better as they don't have that small hole and the flicking is needed to see what is really happening in the system.

Looks like a 5 dollar pressure gauge is your only problem. Pressure gauges have nothing to do with how the pump system works. Gauges are only there for you to see what is going on. You really don't even need a gauge. If the pressure switch is clicking on and off when needed you can be fairly sure it is at 40/60. If the pump never shuts off while a shower is running, you can be sure the CSV is working properly. If after shutting off all taps, if it takes a minute or two before the pump shuts off, you can rest assured everything is still working fine without every looking at a gauge.

With the CSV in control you are not likely to have any pump system problems for decades to come. You will go through a lot of pressure gauges during the life of the CSV and pump system it controls. You may even want to put 1/4" ball valves before each gauge. That way you can shut the water off to the gauge unless you want to see it, which will make them last much longer.

Thanks very much!

 

[Valveman]

Like what Valveman said, gauges don't agree that close! What I do when setting up a system is to shut off the power to the pump, then slowly bleed off the pressure while watching the gauge. When the pressure switch clicks to start the pump, the gauge should slowly drop about another 2 psi, and then quickly drop to zero. that confirms that the preload in the tank is correct.

I do that to see how much air is in the tank without using a tire gauge. With the breaker to the pump off, opening a tap will cause the pressure in the tank to decrease slowly. If there is 38 PSI air in the tank, at 38 PSI the pressure in the system will fall from 38 to zero in one quick thump. That way you know there is 38 PSI air charge in the tank without using a tire gauge. But you do need a good gauge.

 

[JEG in Raleigh]

I do that to see how much air is in the tank without using a tire gauge. With the breaker to the pump off, opening a tap will cause the pressure in the tank to decrease slowly. If there is 38 PSI air in the tank, at 38 PSI the pressure in the system will fall from 38 to zero in one quick thump. That way you know there is 38 PSI air charge in the tank without using a tire gauge. But you do need a good gauge.

Got it, thanks to both of you.