If he's an electrician and not a Whitegoods engineer then you've firstly go the wrong person in to look at the appliance.
Get a tube of...
Your repairer is talking rot. Whirlpool have always supplied end user pcbs. Blanks were used by Whirlpool engineers who could write the software...
You don't need a pcb. Don't know who told you you did but it's 99%certain you don't need it.
4 flashes is a drainage failure.
Get a kettle,...
Yep, model and serial number would help.
Might be able to find the pcb for you then.
ADP8322 is a Whirlpool appliance.
What was the original problem?
What is the part number of the pcb?
Check the top spray arm pipe is locating properly at the rear of the basket.
start light should be flashing. count the flashes.
3 flashes is a heating fault. NTC, heater or main pcb.
You haven't provided the product number or serial number so have to guess at the age.
Continuous flash is a single flash. Single flash is error...
4 flashes is a draining failure.
something stuck in the pump or a blocked drain hose.
Water hammer is a common fault of the inlet valve.
You've pretty well understood how it should work.
Take the side panel off and watch whats...
Intermittent heating can be a dry joint at the heater relay on the pcb.
However, if there's not enough water, it won't heat.
Water level is...
faulty inlet valve, not closing, or faulty main pcb.
As far as I remember the issue is a lack of water in this machine.
If the transfer pipe is clear then the pressure chamber would be the next item...
Its easier if you stick to one thread.
We need the enr number to see what appliance you have.
If you post the enr number and the fd number I'll...
The metering tank to sump hose will be blocked (if you're lucky it won't have blocked the rest).
The alternating valve is fitted between the circulation pump and the pipework feeding the spray arms.
Whirlpool machine rebadged. 4 flashes is a draining failure. If it's draining ok then the fault will lie with the water indicator (pressure...
Well documented failure. Use the search facility and search for Whirlpool and 4 flashes.
Something stuck in the pump?
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