Dishwasher and earth leakage protection

[Utemad]

Hi all.

We just had that great washing machine thread (which I just looked up as ours died yesterday) so now it's time for a dishwasher thread.

My parents just bought a Fisher and Paykel 912T second hand for $50 from a friend at their work. He said it worked fine at his place (replaced as it didn't match the newly renovated kitchen). However at the parent's place it apparently does a great wash but trips the earth leakage unit at the end of each finished load. They have only run it twice so it tripped the earth leakage twice.

My first thoughts is that perhaps it isn't meant to be on an earth leakage circuit. I have seen the instructions for some things at work that say they cannot be on an earth leakage circuit. However it is plugged into the same point as the last dishwasher that didn't trip the earth leakage (it did a terrible wash though and was always breaking down - it was a Simpson).

So any ideas before they call a service tech or electrician?

Thanks.

[ladas]

If it's at the very end of the cycle, then that would be when the heater element comes on to dry the plates etc.,

...........but this could be shot down in flames if it's a cold fill machine and the heater element also heats the water.

So it could be the heater/dryer element ..............or not as the case may be

[RobHay]

seems strange hey! I would rather be suspecting that it would have something to do with the drying mode (heater element), perhaps you need a higher rated fuse / trip thingy, the heater is obviously drawing a massive current and if everything works fine until the drying cycle then thats where I would be looking. Perhaps a Google search will reveal something.

[drivesafe]

Hi Utemad, first off, is your earth leakage switch a separate switch or is it a combined MCB/RCD switch where the circuit breaker and earth leakage switch are one in the same.

Next, can you turn different operations on and off. If you can, try operating the dish washer in different modes and it may isolate a specific operation where the switch trips and this might be the reason why friends didn’t have a problem.

[Utemad]

I haven't actually seen this unit. All this info is from a phone call I received from my Mum today.

I think it is connected to cold water only. I didn't ask though.

The earth leakage and circuit breaker are two seperate units. It is only tripping the earth leakage.

I'll get Mum to try using it without the final drying operation assuming that is the last thing her dishwasher does. We'll see if that trips the earth leakage.

Thanks guys. I'll have more info next cycle :)

[Mudguts]

your dishwasher may or may not be faulty.

1. did your friend have an ELCB controlling the circuit the dishwasher was on, if it was an older home, may not have one.
dishwashers, refrigerators ,freezers and washing machines can all trip ELCB's if there is any leakage to earth , be it from moisture, condensation, dust or fluff that may suck in moisture on humid days .

the fact that it trips at the end of each finished load indicates cooling condensation is causing leakage to earth and the tripping.

refrigerators were notorious for this and were exempt from having to be protected with an elcb protected circuit.

take a look around the wiring and particularly the elements for drips or rust stains , even a squirt with wd40 wouldnt hurt .

it doesnt necessarily mean the dishwasher is faulty , but it shouldnt be ignored either,it could be just "nuisance tripping".

get the serviceman to also check the ELCB to make sure its tripping at the set ma rating.

[seqfisho]

Hi Utemad,

From many years of experience it will be the heating/drying element breaking down and tripping out the RCD. You will need to get the element replaced, be carefull of prices, shop around as F&P can be a bit pricey.

[Utemad]

I just rang Mum and told her to try it out on different cycles. Trying the 'econo dry' first as I presume that means air dry and no heater.

Since it will be undergoing our tests this week, I'll go over and rip the back off it next weekend and make sure it is nothing obvious like a water leak or mouse damage etc.

Thanks for the tips all.

[Utemad]

Hi Utemad,

From many years of experience it will be the heating/drying element breaking down and tripping out the RCD. You will need to get the element replaced, be carefull of prices, shop around as F&P can be a bit pricey.
Thanks. If this is the problem and it is pricey to fix I told her just to run it on 'econo dry' and open the door when it finishes while feeling all warm and fuzzy about helping the environment :)

[Jamo]

It sounds like the element is U/S. I had my Fisher & Paykel on an RCD for years with no problem. Good thing too! Once I had to change a pipe in the bottom that was leaking and I forgot that dishwashers ran on electricity as well as water:eek: .

[Pedro_The_Swift]

and I forgot that dishwashers ran on electricity as well as water:eek: .


is that where the big red nose came from??
;):p

[Utemad]

Well the verdict is it must be the heater element. As when you use the economy dry function the earth leakage does not trip.

So I will have a look at it over the weekend to see if there is anything obviously wrong with it.

[ladas]

Well the verdict is it must be the heater element. As when you use the economy dry function the earth leakage does not trip.

So I will have a look at it over the weekend to see if there is anything obviously wrong with it.

The element is normally quite easy to remove - and to test just use a meter to see if it's going to earth/ground/negative.

When you take the old one out also check below the seal to see if there has been water dripping past the seal - that is of course if the element checks out okay.

And when you put the element back in make sure the oval seal is good - recommend a new one even if the old one 'looks' okay.

Ladas