Separated from: http://www.doityourself.com/forum/el...re-washer.html

Hello,
I replaced the Electric plug on my pressure washer with a standard 3 wire plug. The pressure washer had a GFCI plug, but it corroded internally and I decided to take the salemans' advice and plug into a GFCI extension cord.
The issue: The pressure washer works, but cycles when the wand switch is let go. It cycles about every 5 seconds. It is annoying and I hope not dangerous. So I took the plug apart to check my connections. The cord from the pressure washer is only a two wire, so there is no ground. I looked and looked, the cord is molded and there is only room for the 2 wires.
So, can I fix this? Trying not to go to the expense of a replacement GFCI cord (around $50)
Thank you!

 

Throwing safety out the window for the sake of saving a few bucks. That's a very poor decision.

 

Is this an older pressure washer? I bet the GFCI is sensing the back EMF from the pump motor spinning down causing the GFCI to trip. The original corded GFCI was probably less sensitive to this.

Not sure what I would recommend here, but continuing to trip a GFCI will eventually damage it and not using a GFCI when water and electricity are in close proximity is a bad idea. You could try other GFCI options to see if they are less sensitive to the trigger.

 

I think everyone's confused when you said cycling. I'm assuming it stops and then restarts itself without you having to do anything in that the GFCI is not actually tripping. Is that the case are is the GFCI tripping? They are 2 very distinct problems.

 

Ray................how is a rcd different from a gfi

 

Inexpensive electric pressure washers I am familiar with are suppose to cycle off when the trigger is released.
They use a pressure switch rather than a pressure unloader which is cheaper to manufacture.

Is this how yours is suppose to work?
If so and it cycles on and off when the trigger is released the pump check valve may be faulty.

 

Ray, hair dryers and pressure washers do indeed use a GFCI plug. Air conditioners use a RCD/LCDI device.

 

Thanks Justin. I was postulating only on my knowledge of A/Cs. I didn't know there was a difference. Do you have any links on this?

 

I don't have any off the top of my head all I have is experience from people giving me broken stuff, and me taking them off. (Who can't refuse a free GFCI plug?)

 

A residual current device is the same thing as a ground fault circuit interrupter. The term RCD is used a lot in Europe.

(added later) There is a device called a leak current detection interrupter, sometimes built into air conditioner power plugs (cord caps) that works somewhat like a GFCI. As defined, LCDI is not necessarily sensitive enough to trip if there is a fault current large enough to electrocute someone. LCDI is usually accompanied by a power cord whose equipment grounding conductor is a mesh similar to that in an electronic coax cable and the intent is to cut the power and prevent a fire if the cord become frayed. GFCI/RCD will also cut the power due to a frayed cord where a fault to the EGC occurred.

Is the extension cord you are using too long or too thin, resulting in excessive voltage drops accompanying the peak electrical draws and then the washer pump cannot function over all the normal pressure fluctuations occurring during usage?

Does the pressure washer contain a "pressure tank" to help maintain a constant pressure? If there is a pressure tank and that tank does not have an air cushion inside then the washer unit will operate erratically with the pump possibly shutting off due to pressure fluctuations going too high (and possibly restarting automatically after a short delay each time).

See the instructions regarding the existence of a pressure tank.