Faulty Bosch Dishwasher

[jims-terrano]

Didn’t want this taking over Ricks thread.

My dishwasher has decided to cause problems and of course has to happen when I least need this to happen. It’s amazing when you all go out to work and the rest of life that you become to rely on them.

Anyway a while ago we noticed the pipes in the house had started to hammer as it was filling which they never used to do. It’s gradually got worse at washing until now it seems to make things dirtier than when they went it.

Cleaned the filters and wife has cleaned the spray bars. Dishes have always been rinsed before going in.
It gets hot.
When I open door it seems to throw a lot of water around inside when running.
The sump area where the filters are doesn’t seem to contain any more water than normal so when filters are in you cannot see water level.
It seems to of stopped washing the powder out of the little box when it opens. Have been using some solid powder tabs which seem fine. Have tried those all in one tabs but it doesn’t desolve the outer coating.

Just checked filters again and found some kind of grit. I’ve seen a few bits on the net about the impeller so I’m wondering if the grit is rusted out impeller shaft or something.

So has anyone got any more ideas please?

 

[rayf3262]

The water metering tank under the LH side cover may be partially blocked with scale or organic matter. It is made of translucent polythene so easy to see foreign matter.
Remove tank and clean with descaler or bleech as appropriate. It may need a long soak.

 

[solarman216]

Among the problems I have had with dishwashers are debris in the wash pump, usually something that has broken off inside as the filters stop external debris, pump impeller detaching from the shaft(they are usually plastic), water level too low due to water level pressure switch failure or pipe to it part blocked or the inverted cup that traps the air to the switch gunged up, worn out spinner bearings/shaft allowing too much water leakage, as for the pump issues the only way to check is remove it, Rick

 

[macabethiel]

Dishwasher Faults

I assume you have cleaned the bottom filter Mesh etc.

I had a previous Bosch (still have one) dishwasher that faulted when just out of warranty after lots of pulling it out from under the worktop I realised it was not emptying properly all the time. Sometimes it worked other times it did not.

I removed the motor that empties the machine it had a little propellor on the end of the shaft. I found the motor worked fine except the rotor part (coil & magnets) was spinning on the shaft only turning the propellor at about a fraction of the required speed. Not sure how the shaft was supposed to be fixed to the motor but you could turn the plastic propellor and the motor magnets stayed still as the shaft was not fixed to the rotor !!

As a new motor was then only about £15 I replaced it - it carried on working until it was about 8 years old then programme switch failed so scrapped.

I toyed with the idea of drilling into one of the magnets and putting in a grub screw to pinch the shaft - decided it was such a pain to have to pull it out & get at the motor that £15 was cheap enough!

 

[jims-terrano]

Already fixed the PCB on this one a few years ago. It had stopped heating up so after browsing YouTube once I saw a fault that was basically two relays which had dry joints on it. Took mine to bits and sure enough exactly the same on mine. Cleaned board and resoldered the joints happy days. We are going to look at money this week and see if it’s worth just buying a new one as it must be about 14 15 years old. If not will maybe pull it out of the kitchen unitand see what I can find but it’s a built in one so a lot of messing about.

 

[rayf3262]

Anyway a while ago we noticed the pipes in the house had started to hammer as it was filling which they never used to do.

From an appliance repair forum:

Bosch dishwasher water hammer:
I have a Bosch SGS56E02GB/45 dishwasher which has recently started causing a hammering in the pipework when it fills.

I've resolved it:
The float in the pressure chamber which registers the water level in the sump was not sinking to the bottom of the chamber when the machine emptied due to an accumulation of residue.
The motion of the water entering on the fill cycle was causing the float to rock/bounce, and as it was at the top of it's range, it kept triggering the 'over-fill' switch with every bounce.

I took the pressure chamber apart and cleaned it out, and the problem has gone.

If I'd have taken the left side panel off and watched what was happening when the noise was being made, I'd have diagnosed it a lot sooner!

Hopefully this helps someone in the future.

 

[jims-terrano]

Interesting, is that the same tank or chamber that you mentioned earlier?

See if I can summon up the round things to try taking it all apart then.

 

[rayf3262]

Its the next part in the fill chain from the metering tank/matrix. The pressure chamber is fed from the lower RH corner of the metering tank.
Both of these parts on Bosch/Siemens/Neff dishwashers commonly suffer from from crud building up in both of these components. My view is for the cost of a couple of hours work the machine should keep going for good while.
Take a look here:
https://www.youtube.com/watch?v=O6IPWiHi104

 

[Davey Boy]

As said Jim...
The clear plastic pipework (metering tank) behind the left hand side panel needs a damn good flushing out.
I had this issue with our Siemens.
Oh, and give the water you can see remaining in the sump under the big mesh filter a really good slap and agitation, as the float switch in ther can get sticky too.