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This dishwasher has 3 problems:-
1. Stalls in wash cycle and water temperature is MUCH greater than normal
2. Salt level doesn’t decrease substantially
3. Wash (when it was working) leave dishes dirty1. I have assumed that the cause of high temperature is that the NTC sensor is likely to be faulty. I believe that I have located this on the back of the heater, and have removed the two mounting bolts and loosened the cable-tie. Can I just pull on the heater unit to free it from the circulating pump and sump ?
2. I think that I’ve found the valve solenoid on the base of the salt container, and the winding is open-circuit. If I remove the two mounting screws to remove the solenoid, will the water contained flow out ? (How do I drain it beforehand ?)
3. On the LHS, there is a large plastic item which appears to have a load of muck in two sections. How do I remove this from the machine to clean it ?(Hopefully, I have added 2 photos, one of base and one of RHS – however, I’m new to this forum so can’t be sure I’ve done it right !!)
Many thanks in advance for any advice offered !!
Re: Bosch SGS43C12GB/19 dismantling advice
1) The high temp and poor wash most likely indicate that the water diverter (integral part of heater assy) has failed = New heater unit.
2) Remove solenoid and fit new one quickly to avoid any spillage of saline solution. 😉
3) Unclip blue fill tube. Remove central matrix fixing screw, unscrew collar inside tub and gently ease matrix up and off salt container.
Re: Bosch SGS43C12GB/19 dismantling advice
Hi Martin, Many thanks for your help. After the removal of the two mounting bolts, does the heater assembly just pull out of the seals ? Or does the circulating pump have to be removed first ? If so, does the pump just pull out of the sump ? As you can tell, I’m a bit confused on this assembly !! I assume that the black unit on the side of the heater assembly is the water diverter – is this usually a mechanical or electrical failure ? Once again, many thanks for your advice !
Re: Bosch SGS43C12GB/19 dismantling advice
To remove the heater you release the crimped hose clamp that attaches it to the circulation pump AND the two securing screws (not bolts) and ease it away from both the pump and tub.
The black motorised unit on the heater is the water diverter. (Unserviceable).
To first confirm whether that unit is at fault you will need to perform a simple test. Namely, turn on the washing cycle and check that the top and bottom spray arms rotate alternately (every 60 seconds) whilst the circulating pump is running. If only one or neither do, yet there is sufficient water in the tub, then chances are the diverter has seized.
Re: Bosch SGS43C12GB/19 dismantling advice
Hi Martin,
Did as you suggested and ran a Quick Wash.
In the first cycle, I confirmed that both spray arms rotated alternately every minute. This cycle lasted about 12 mins before it pumped out. (The water DID seem to be hotter than 35 deg).
The second cycle seemed very short (about 4 mins)
The third cycle lasted a long time (about 20 minutes) and I thought that it was largely on bottom spray arm. The water temperature increased to 48 deg (or ultimately even higher) before it pumped out. (I think the other spray arm DID come into play in the latter part of the cycle) The water then was VERY hot !
I’m now beginning to wonder whether this is a control board issue rather than the NTC sensor. Is the extent of each cycle determined by water temperature or only time ? I also notice that pump-out seems to be start/stop and takes 3 or 4 cycles to fully empty – is this normal ? Would appreciate your thoughts on what the next step should be – I’m tempted to get the NTC sensor out and test it in isolation.Re: Bosch SGS43C12GB/19 dismantling advice
That test rules out heater or NTC problems, which is good :tup:
NTC’s are pretty darn reliable so I would not venture there. And yes when the NTC signals temperature attained the programmer should proceed. The fact that the programmer does proceed indicates that it too is performing as it should. There’s no halfway house here. 😉
The drain pump could be an issue though. Filling too especially can be a caution and the Impellor Jug device the usual culprit. Symptoms = Irratic sequence of filling then draining immediately is classic Impeller Jug trouble.
The correct water level by the way is just lapping the salt cap thread.
Re: Bosch SGS43C12GB/19 dismantling advice
Hi Martin,
I may not have mentioned this sufficiently before, but the fundamental problem with this dishwasher is that sometimes it does NOT finish the wash but “sticks” in a heating/washing cycle – hence why I have been concentrating on the NTC sensor.
I have removed control board for a quick look – nothing obvious.
I then did another run yesterday (without opening door to check spray arm rotation or measure water temperature, so that programmer was not “interrupted”) However, I DID did do temperature measurements during pump-out as follows:_
Phase 1, duration = 12 mins, end temperature 48 deg C
Phase 2, duration = 4 mins, end temperature 32 deg C (is this cold rinse ?)
Phase 3, duration = 11 mins, end temperature >>50 deg C (highest point on thermometer !!)
(Obviously, complete process did end without “sticking” on this run)
So, in order to eliminate it, I removed NTC and tested it:-
50KOhm at ambient, falling to about 10KOhm at high temperature.
So that seems OK (as you correctly predicted !!)
I am now planning to remove control board again, check for intermittency on plugs/wiring, and examine PCB for dry joints in that area.
If that all checks out, I’m struggling to know where to go next !
Incidently, there is a container next to the salt reservoir ( about the same size) and is “filled” with brown liquid. What is that ??
Also, does the matrix retainer (plastic collar inside ) rotate normally (anti-clock to release) ?. I have tried but am afraid that I might break it !!
As ever, many thanks for your help – much appreciated !Re: Bosch SGS43C12GB/19 dismantling advice
The chamber containing the brown substance is the Ion Exchanger part of the water softening system.It contains polymer resin ‘beads’ a vital ingredient to the water softening process.
The matrix collar is a conventional thread (anti-clock to unscrew)
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