How to Replace a Water Pump Pressure Control Switch InspectAPedia® -
How to Replace a Water Pressure Control Switch that Sticks "ON" or "OFF" or is irregular
How to Find & Adjust the Water Pump Pressure Control Switch, what the pump pressure switch looks like, where is it located on the water system?
Well pump & water tank diagnosis & repair procedures
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This article describes How to Replace a Water Pressure Control Switch which is not working properly.
In the sketch above the water pump pressure control switch is item #4 - we show this switch in more details in photographs provided below.
Readers of this document should also See WATER PUMP PRESSURE CONTROL REPAIR and WATER PUMP PRESSURE CONTROL ADJUSTMENT.
And at WATER TANK BLADDER PRESSURE ADJUSTMENT we discuss fine tuning the pump pressure control switch to work perfectly with the exact air pressure pre-charge in a bladder type well tank.
How to Remove and Replace a Water Pump Pressure Control Switch
Here we discuss the detailed steps to follow in removing and replacing a water pump pressure control switch. If you want to take apart, inspect, and try cleaning up an old pump control, use the directions here to remove or reinstall it, use the information at WATER PUMP PRESSURE CONTROL REPAIR to inspect and clean the control.
Here are a few tips that will make removing and replacing the water pump control switch easier, and which will reduce the water spillage (or spray) into the room during this operation.
Turn off electrical power to the water pump. If you simply unscrew the pump control without first turning off the pump and taking pressure off of the water tank and pump, you will have a fountain of water squirting all over the place.
If you make this mistake and if you can't easily simply screw the old parts right back in to stop the leak, (you'll only do it once) don't panic - it's just water. Just turn off the pump and open a nearby valve to take water pressure off of the system.
If the pressure control switch is mounted high, say on top of a well pump which is itself on top of a water tank, all you need to do is take pressure off the water tank – don’t need to drain it fully.
Disconnect electrical wiring from the water pump control. SAFETY WARNING: you can be killed by electrocution. Be sure that electrical power has been turned off, confirm that power is off using a neon tester or VOM. If you are not skilled and trained in this work, hire an electrician or plumber to do these tasks.
Mark the electrical wires and their proper connection points on the water pressure control switch. If you're proceeding on your own, mark and label each wire and each terminal that it was connected to so that you can replace the wiring correctly later.
Remove water pressure from the water tank and pump by opening a nearby faucet or tub, or by connecting a garden hose to the water tank drain and running the hose outside. You might not need to drain all of the water out of the water tank:
Water tank full drain down method #1:
If the pump pressure control switch is mounted at the bottom of the water tank
– you can drain the water tank completely, but watch out for losing pump prime on some older types of pumps
– take some water into reserve containers in case re priming of an old jet pump is needed at the end of this repair.
This will not be a concern the well pump is a submersible one down in the well since such pumps are self-priming.
Water tank partial drain down method #2:
you can take the water pressure off of the water tank, down to say 5 or 10 psi, and speed up the repair process by following these steps:
Enlist the aid of an accomplice whose role we'll explain in a minute
Have all water pump control repair parts you might need close at hand and prepared for use
a new little riser pipe
a pipe plug of the same thread and diameter as the pump control mounting pipe you’re removing
Pipe dope or teflon tape
All new parts you intend to replace
Unscrew the old parts
Block leaking water with a finger or a pipe plug.
As you remove them and water begins to flow out of the opening where the control was mounted, the accomplice simply puts his/her finger over the hole and keeps it there while you do your control checkout or prepare the replacement to screw in – it’s easy to hold back 5 psi with a finger over a small hole.
If you don’t have an assistant, remove the old parts, and through the flowing water out of the threaded opening, screw in the pipe plug you bought for that purpose (cheap assistant) to close the leak, then go on to investigate the control or prepare and re-install the new one.
Replace the pump pressure control parts with the new ones or the repaired ones you've got at hand.
we like to prepare the new replacement parts with pipe dope or teflon tape before taking apart the old ones - that makes it quicker and neater in reassembling the pump pressure control switch with minimum water spillage.
Reconnect the electrical wiring to the water pump control just as the previous control was wired. For a 120V circuit, there will be four electrical wires, two line-in wires (hot and neutral wires) from the power source are connected to two screws which may be indicated as "Line" by markings on the switch, and two line-out wires (hot and neutral wires) bringing power out of the control and on to the water pump.
If your pump pressure control switch is controlling a higher capacity submersible well pump, the electrical wires leaving the control may feed a separate heavy duty pump relay switch rather than going directly to the water pump. Well pump relays are discussed at WATER PUMP RELAY SWITCH.
Turn off any faucets you opened earlier to remove pressure from the water system.
Turn the water pump electrical power back on
Watch the water tank pressure gauge, and when you have about 20 psi in the system (our gauge reading shown here is a bit too high) turn the water pump power back off and check the system for leaks.
Wipe dry any wet parts, especially around the bottom of the pump control and where the pump control mounting pipe or fitting mounts into the water pump or water tank fitting.
Inspect your plumbing connections closely for water seeping out - if you have leaks go back to step 1 or 2 and re-make your connections with better preparation of the threads with pipe dope or teflon tape.
When you confirm that there are no water leaks, turn your pump power back on and the system should operate normally.
IF the well pump is still not turning on and off properly you probably have another or a different problem. See the other water pressure and water pump control diagnostic articles listed at the left of these pages.
A Guide to Building Water Pressure by Adjusting or Repairing the Water Pump Pressure Control Switch
How to Adjust Water Pump Pressure: The detailed, step by step procedure for inspecting and adjusting the water pressure control switch is
discussed in detail at ADJUST PUMP PRESSURE CONTROL.
Diagnosing Water Pump Short Cycling on and off: If your water pump is clicking on and off too often or quite rapidly see SHORT CYCLING.
Diagnosing & Repairing Lost Air in the Water Tank: The problem of lost air in the water pressure tank along with how to correct that condition are discussed
beginning at SIGNS OF AIR LOSS.
Diagnosing & Repairing a Water Pressure Control or Water Pump Control Switch: We discuss diagnosing and repairing a water pressure control switch that sticks "on" or "off" or simply won't operate, at water pump Pressure Switch Repairs.
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General water testing and corrective measure advice: contact your local health department.
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