Pressure Pump Repair

Customer brought in a Chinese pressure pump that is sold by the hardware stores for repair. Plugging in showed the pump did not operate and the error LED on the controller was on. Removing the controller cover revealed the PCB with a terminal block for the pump and the mains input. Removing the pump pump wires from the terminal block and connecting suicide leads through my inline ammeter¹caused the motor to run drawing about 1.5A which was reasonable for the capacitor run pump motor². The motor was tested for a very short time as the pump was running dry and the water cools and lubricates the pump seal. This proved the the pump was OK and the problem was in the controller PVB.

I remember reading about a repair to a pressure pump controller in Silicon Chip Serviceman's log:(Vol 25, No.5 May 2012 page 63). After hunting the magazine out and reading the article it found the 1μF 240V capacitor faulty. I measured its value and found it to be about 0.1μF in circuit and it measure the same after removing from the PCB. The faulty capacitor was replaced, with two 0.47μF in parallel, being the same physical size made the replacement a little more difficult in the limited space. Putting it altogether and plugging in cause the pump to operate.

A little information and someone else experience can can make a repair job easier. This repair was much cheaper than replacing the pressure switch controller.

More information on this can be found in my book: “Australian Washing Machine Repairs” Lindsay Alford:

1: Appendix A1

2: Section F7