Baumatic Dishwasher trips RCD..how can I prove I'm right?

[tonyapple]

Hi there

I "believe" that my Baumatic dishwasher is causing the RCD on my consumer unit to trip very occasionally. The first time the RCD tripped in the house was about a year a go (although in that incident I don't remember whether the dishwasher was running or not). Since then it has tripped about a half dozen times and each time the dishwasher has been on.

Normally once the RCD is reset I don't experience another trip for weeks or even months.

When the RCD does trip I usually have to wait about 3-4 minutes before the RCD will allow itself to reset. In other words if I push the RCD switch back up/on immediately after a trip it doesn't "click and hold" it just pings back, but if I try again after a few minutes it will eventually remain in place.

On Saturday night the RCD tripped again whislt the dishwasher was on. I didn't turn anything off and after a few minutes reset the RCD. The dishwasher started again but then around 5 minutes later the RCD tripped again. This time I switched the dishwasher off at the socket (but left the plug in) waited the usual few minutes and reset the RCD. The power has been on in the hosue since with no issues. Its worth pointing out that on saturday night I had quite a few things on at the same time as the dishwasher (eg kettle, 2kW Ac unit, projector, PC etc).

Now it certainly sounds like its the dishwasher causing the problem so I'm intending to either replace it or repair it. My question is is there a definitive test that I can do to prove that its the dishwasher? Also since the dishwasher was stopped in midcycle on Saturday night, its still got a lot of water in it...any idea how to get it to drain without having to power it on again?

Many thanks for your help.

Advice for a new dishwasher also welcome. I've already spent £90 on this baumatic this year just to fix the hinge......

 

[JohnD]

it is possible that your dishwasher is the problem

However, if, as I gather from your post, you only have one RCD to protect the whole house (this is very poor design) then it is entirely possible that you have ten other earth faults at 3mA each, or twenty at 1.5mA each, or three at 10 mA each, or a background leakage of 29mA, and the dishwasher just happens to add a tiny bit more that pushes you over the trip current.

Have you got any sockets that are not RCD protected, for example on the cooker switch?

If you say that you have to wait a few minutes before resetting, pull out the plug of the dishwasher and try to reset it immediately. An unplugged dishwasher cannot give a fault current.

The delay might be due to dampness somewhere caused by a water leak and taking a little while to evaporate. Have a look under your suspect machine. It might be a trivial fault like a loose hose or seal.

Most earth leakages are on watery appliances such as washing machines, kettles, tea urns, immersion heaters, boilers and their pumps, washing machines, dishwashers; or on appliances with a heating element such as ovens, immersion heaters, kettles, washing machines and dishwashers.

PCs always have a small earth leakage due to their power supply design.

If you want a new dishwasher, get a Bosch, or a Miele if you can afford it.

You can drain the water out of a dishwasher by taking the flexible waste pipe out of its drain and lying in flat on the floor (preferably into a bucket) and the water will run out).

 

[tonyapple]

If you say that you have to wait a few minutes before resetting, pull out the plug of the dishwasher and try to reset it immediately. An unplugged dishwasher cannot give a fault current.

Excellent idea, will try tonight...

you only have one RCD to protect the whole house (this is very poor design)

i'm reasonably new to this, the RCD only protects the sockets downstairs (which includes the kitchen). The upstairs sockets and both floors' lighting however seem to be excluded from RCD. Unfortunately this design rules out switching the dishwasher (or fridge freezer!) over to a non RCD circuit. (unless i move my kitchen upstairs LOL). Would be interested to read/hear what is a more sensible RCD config.

I'll give the draining a go tonight too, thanks so much for your post, exactly the kind of advice I was looking for.

 

[JohnD]

Unfortunately this design rules out switching the dishwasher (or fridge freezer!) over to a non RCD circuit.

buy a 13A extension lead and try it.

Have you got a cooker circuit? Is it on the RCD? does it have a socket on the switch?

You say you have one RCD that protects the downstairs sockets, this is in some ways better than having one that protect the whole house. It used to be done that way as it protects sockets that can reasonably be expected to supply equipment used outside (such as lawnmowers or car tools). Post a photo of your consumer unit (fusebox) with the door open (don't take the cover off yet) and one showing the meter, incoming supply, consumer unit, and the various cables around and between them (especially any green and yellow ones). this will give some ideas of what you might do next.

//www.diynot.com/forums/viewtopic.php?t=129539

 

[tonyapple]

Have you got a cooker circuit? Is it on the RCD? does it have a socket on the switch?

cooker is on its own circuit with a single socket outlet in the kitchen but this circuit is on the "lower" half of the consumer unit which is RCD protected.

I can certainly run a 13A extension from one of the upstairs sockets for testing the dishwasher but clearly this won't work long term LOL.

I'll take pics and post them tonight or when i get a chance later in the week. Again very grateful for the help.

 

[JohnD]

BTW you can get an RCD adaptor from a hardware or gardening shop, one of those things that you plug a lawnmower in to give protection against cutting the cable - if you plug your dishwasher into that, via an extension lead from a non-RCD upstairs socket, you will see if the dishwasher is the main culprit.

But I would also have a look for signs of a water leak.