Bosch dishwasher not filling SGS43A52

[boselecta]

SGS43A52 GB02

Machine pumps out, then wash pump comes on does not even try to take any water.
Cleared transfer hose and air chamber. Machine does not have flow meter.

any ideas guys?

[Pigpen4]

Re: Bosch dishwasher not filling SGS43A52

Although I’m fairly new to this, it sounds like it thinks it’s got enough water in, if it’s operating the main pump.

The pressure switch is located on the instantaneous water heater, between the two heater element connectors, and is operated via a diaphragm which is part of the seal where the element fits into its housing.

Is the microswitch stuck?
If so, it can be easily prised out of the mounting for replacement.

If not, it may be gunked up with grease on the inside of it, if the machine’s grotty.

The elements do come out after a struggle (in fact, I replaced an element from a more expensive instantaneous heater lump of components with that of a cheaper lump the other day to save a customer £35 – same heater element, just different ancilliary parts built onto the lump, but you can’t seem to buy the element independently, unless someone out there knows differently?!

As I say, I’m new to this (only started in January this year), so this is almost certainly not an exhaustive list of possible causes. I’m sure some wiser, more experienced practicianers out there will have more solutions, but at least it’s a place to start looking.

Hope that helps,
Pigpen.

[nomadPaul]

Just a little info Pigpen. The microswitch on the IWH has nothing to do with water levels. It’s a safety pressure switch to ensure the heater doesn’t operate with insuffecient water levels. the water level on these machines is controlled by the pressure chamber on the left hand side .

Bo’ , i’d definitely be looking at the LHS pressure chamber again , maybe the microswitch at the top of the chamber itself. If this is stuck in a closed circuit position , it’ll think its already full of water. It’s only the signal from this switch that will supply the board with a signal concerning the level. If the pressure chamber is 100{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} working , then you may be looking at a board fault.

[boselecta]

Hi pigpen
Thanks for replying. My understanding is that the microswitch on the heater is to prevent the heater coming on with no water inside, not to do with filling.
The pressure system is connected to the air chamber.

[Pigpen4]

Re: Bosch dishwasher not filling SGS43A52

My apologies, and thanks for the corrections.
Of course, it makes sense that that’s what that microswitch is for.
I think I’ll keep my head down and learn a bit more before jumping in feet first in future!!
As I said, I’m still learning … 😳

[nomadPaul]

Re: Bosch dishwasher not filling SGS43A52

Pigpen4 wrote:My apologies, and thanks for the corrections.
Of course, it makes sense that that’s what that microswitch is for.
I think I’ll keep my head down and learn a bit more before jumping in feet first in future!!
As I said, I’m still learning … 😳

Mate , this is one of the best place’s to learn. You can’t beat advice from experienced engineers. I’m a mere learner compared to most on here and my general knowledge of appliances has increased remarkadly since joining…..even though i don’t work on 90{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} of the stuff mentioned 😀

[boselecta]

Thanks for replying guys,
went back today and it was indeed one of the pressure chamber microswitches faulty and she now fills.
Thats the first one of these I have known to go down.

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