Pump Pressure Control Switch Adjustments

Pressure Control Switch Calibration Q&A

Do I use a pressure gauge to set the pump cut-in and cut-out?

Do you use the pressure gauge to set the psi by what it shows when the switch kicks on and off?

It says to set at 28 psi.

But there are no numbers on the switch, how do you know what you are setting it at?

Having a problem, just replaced my water pressure tank. Have a submersible pump. Problem is that when running the water the pressure switch is short cycling. it will go off and on about 4 times real fast then stop about 20 seconds then do that again. How do I adjust it ? On 2018-10-16 by Teresa Jarrell

by (mod) - how to determine the pressures at which the pump control is turning ON and OFF

Teresa

You can use an independent pressure gauge Teresa or you can see what the pressure is on the gauge that's attached to your water system.

To use an independent gauge - it's easy and inexpensive - see WATER PRESSURE MEASUREMENT - how to buy or make your own portable water pressure measurement gauge

When the pump STOPS and with NO water running in the building, read the water pressure system at the pressure gauge you'll find on or near the pump or water tank.

About the short cycling of your water pump, most likely your water tank has lost its air-charge.

But if the short cycling is extremely rapid I would look first for a closed valve on the outlet from the water system and second for problem with water not entering the tank. I've also found this problem when there is a water filter installed and the water filter is clogged.

Sometimes then a pressure tank the bladder can get stuck to the tank bottom and refuse to accept water. Both of those conditions can cause rapid short cycling.

See the diagnosis and repair steps at WATER PUMP SHORT CYCLING - home

Also see WATER PRESSURE GAUGE ACCURACY 

Pressure Controls for Multiple Water Pumps in Tandem

Pressure control settings when using two water pumps on the same system: ok to have manual pump cut-off?

I want to set our pressure switch settings for water

Pump #1 should be start on 4 kg/cm2 and stopped on 6 kg/cm2.

Pump #2 should start only 3 kg/cm2 and off manually - On 2018-02-08 by Abhimanyu Mishra

Suggestions by (mod) - each pump needs its own pressure control

Mishra

You cannot control two different pumps at different operating pressures using a single pump pressure control switch.

You need a dedicated pressure control for each water pump.

Then, if both pumps are feeding the same water system and tank, the controls need to be set to work consistently.

By your description, IF Pump #1 has adequate capacity and IF the water capacity is constant, then pressure will never fall below 4 kg/cm2 so Pump #2 would never run.

And when IF Pump #1 is capable of pumping to any pressure above its CUT-ON or CUT-IN pressure, Pump #3 will never run.

Details:

Although our pressure examples are in PSI, the principles and adjustments of a pressure switch are the same regardless of the units in which pressure is being reported.

4 kg/cm2 is about 57 psi and 6 kg/cm2 is about 85 psi (for other readers).

If your pump control switch works like the one shown in the article above you simply need to watch the pressure reading on your system's pressure gauge.

Run water, watch the pressure fall, note the pressure at which the pump starts. Adjust the switch to raise or lower the starting pressure accordingly. That's the "CUT IN" pressure.

You cannot however use the same control on the same single water system to operate at two different pressure ranges.

So I don't understand how your second pump control example would work unless you mean it's for a different system.

Watch out: In any event you should NOT set up a switch that will never turn the pump OFF since under some conditions the pump pressure could blow out a pressure tank or pipe that could in turn injure or even kill someone nearby.