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Checking the Pressure Switch
:
If your motor is not running and you’ve checked the following: for loose wiring connections, fuse, the
switch on the lead wire was “ON” and made sure you were connected to a fully charged battery and
everything is fine, but the motor won’t run, then it’s time to check to see if the pressure switch is bad.
Remove the cover off the 1” square box (pressure switch) on the head of the pump, the cover is
held on by one phillips-head screw. This will expose the two red wires.
With the pump connected to a good 12 volt power source and everything on.
Slip the two red wires off the terminals and touch them together.
If the motor runs, it means the pressure switch is bad and needs to be replaced.
If it still doesn’t run, try bypassing the switch in the lead wire or using another lead wire. Even if a
tester shows power to the pressure switch, it still could be the switch in the wire that is causing the
problem. If still not responsive, use a voltmeter or electrical tester to make sure you are getting power
to the head of the pump, as it could possibly be something in one of the wires or even the lead wire
assembly may need to be replaced.
Warning:
It is NOT recommended to run the pump this way, as the pump will continue to run and not
shut off.
This could result in blown hoses when all discharges are closed. Also, this could result in premature
failure of the pump completely.
Cleaning the Check Valve
:
If you’re experiencing little to no pressure or the pump is not priming and you’ve checked your filter
screen and it’s clean, you may need to clean the check valve.
Remove the head of the pump, which is held on by about 6-7 screws.
The first piece inside the head of the pump is called a check valve, it’s the part responsible for building up pressure and
pumping water/solution through the lines.
Clean the check valve under hot, soapy water (such as a good grade dish soap).
Give it a very light scrubbing with something like an old toothbrush, something with soft bristles.
Then let it soak for about an hour or so in the hot soapy solution and replace in the pump and reassemble the
pump.
Most times this will restore most, if not all of the prime of a pump.
Try another 12-Volt battery
Quarter turn at a time clockwise until surging stops
Check that shut-off valve on inlet (if applicable) is open
Troubleshooting
Pump will not run:
Check for loose wiring
Make sure the ON/OFF switch is on
Check the fuse
Check for defective pressure switch
Low Pressure/Low Flow:
Check for a clogged strainer
Check for proper voltage
Check for worn or dirty check valve
Pump surges:
Low flow may cause pump to surge
Spray wand is adjusted for a small or fine spray pattern
Slightly open bypass (if applicable) to overcome
If needed, pressure switch may need to be adjusted
Pump continues to run:
Bypass (if applicable) is not completely closed
System has leaks
Check for worn or dirty check valve
Fuse blows:
Excessive voltage
Improper adjustment of pressure switch
Damaged or defective wiring harness
Defective pressure switch