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Hi,
I wonder if you could help me?!
I have a 6 year old Whirlpool ADG7540/1 dishwasher. It’s run perfectly for 6 years until last week when I noticed it was not washing the items properly. It is clear that it is not heating the water.
It wasn’t showing any error. It was doing the full wash – just not heating the water.
I’ve read the other topics on here which are very helpful.
I thought I would try to disconnect the NTC module.
I disconnected the NTC connector from the main board and switched on the machine. It beeped at me a lot and started trying to drain.
I switched it off and re-connected the NTC. When I switched it on it’s just constantly trying to drain. Even if no program is selected, it continues to try to drain. It only stops if I switch it off or if I open the door.
I powered it off at the wall for 1 min. Then switched it on. It gave a single beep then was waiting for a program. I selected rinse, pressed go, and now it’s back to constantly trying to drain again.
It then stopped trying to drain, and is constantly beeping and showing 6 flashes of the Go LED.
Any ideas?
From reading the other similar topics, it seems to be either the water heater, main board, or the NTC.
Thanks!
Giles.
Re: Whirlpool ADG7540/1 Not Heating Water
NTC has nothing whatsoever to do with your problem. Leave it alone as they’re notoriously fickle beasties.
The heater needs a resistance check (approx 25 ohms) to prove whether or not it works.
6 flashes is to do with water level control. It’s possible that you have disturbed the connections to the flow meter in the water matrix under the left hand side, it’s equally possible that the sludge in the water indicator (black grid in the sump) is now jamming the switch in the full position.
Power off before going back in, please.
Penguin45.
Re: Whirlpool ADG7540/1 Not Heating Water
Thanks for your response.
Later last night, after I’d re-powered the dishwasher, it started up as normal. No error code.
I selected the short, 40c, wash. It ran through the wash, but water remained cold throughout.
I will check the heater resistance tonight and report back! Any other checks I should do?
Thanks!
G.
Re: Whirlpool ADG7540/1 Not Heating Water
Hi,
The water heater shows resistance of 24.6k ohms.
What do you suggest I do next?
Thanks,
Giles.
Re: Whirlpool ADG7540/1 Not Heating Water
The NTC connector at the main PCB is showing electrical resistance of 5.27k ohms. Does any one know if that’s correct?
Thanks.
Giles.
Re: Whirlpool ADG7540/1 Not Heating Water
I’ve just measured the AC Volts of the Water Heater connector during a short 40c wash.
It remained at 0.003v throughout.
I dug out the PCB to see if I could see any thing that might have blown, but it all looks clean.
Any suggestions? New PCB?
G.
Re: Whirlpool ADG7540/1 Not Heating Water
Hi Giles,
25 ohms on the heater is about right. NTC reading in kOhms is generally acceptable. No supply to the heater more or less has to pcb, assuming that you have continuity back to the pcb.Penguin45.
Re: Whirlpool ADG7540/1 Not Heating Water
I poured very hot water in to the dishwasher last night and watched the NTC resistance on the multi-meter.
Cold resistance on the NTC started at 5.26k ohms, after I added the hot water the resistance steadily fell to 4.76k ohms, then it suddenly jumped to 12 k ohms and steadily fell to 11.55k ohms, then started climbing all the way up to 15k ohms, then it jumped to 5.3k ohms again and remained there.
Perhaps the NTC is faulty and therefore telling the PCB not to provide power to thewater heater.
I ran a short 40c wash, but again, no hot water was produced.
I’m reluctant to buy a £150 pcb, if it’s actually the NTC that is at fault.
What are your thoughts Penguin? Thanks for your help BTW – I really appreciate it.
😀
Re: Whirlpool ADG7540/1 Not Heating Water
NTC device should read approximately 60kOhms at room temperature, 40kOhms at 40c and 12kOhms at 60c. Looks like your readings are way off, in fact the computer may think that it’s already at wash temperature!
NTC device is a damn site cheaper than the computer, so that’s probably the way to go. You can get one HERE.
Penguin45.
Re: Whirlpool ADG7540/1 Not Heating Water
Hi Guys,
The NTC arrived yesterday. I fitted it tonight and we have hot water!
I ran a 40c short wash and we had steam and everything – it was amazing! It ran through whole wash and stopped as expected.
Thanks for your help.
I then put all the bits back on the dishwasher and pushed it back in to its home.
PROBLEM!
I switched it back on and it’s draining for about 1 min, then beeping and giving me an error code of 6 flashes of the LED. It will not run any programs.
😥
I saw this error code about a week ago, but it just disappeared. I see that you said it was to do with water level control.
Can you suggest how I solve this new issue?
Thanks,
Giles.
Re: Whirlpool ADG7540/1 Not Heating Water
One down, one to go…..
This can be one of several problems. Start by removing all the filters and looking into the sump at the 3 o’clock position – you should see a black grid. This is the water level indicator. The grid is particularly prone to filling up with fatty deposits and jamming the switch in the full position. The microswitch on the other side is a “light action” device and can fail to reset to empty over time as the spring weakens. If it looks “gungy” a good scrub out with hot water and a toothbrush may clear it.
Alternatively, the flow meter in the water chamber on the left hand side may be misbehaving. This is a waterwheel device, using a magnet and reed switch to generate pulses which the computer counts to work out how fast it’s filling. The connector is particularly prone to oxidisation problems. A thorough clean of the pcb contacts and a pinch of the connector will often solve it.
HTH,Penguin45.
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