Its the pre heat function,
The Expansion vessel requires Repair/Replacing. Should not cost to much
That P.C.B (248074) was supersede by 5112380 a long time ago. Be careful what you wish for.
If your that desperate look on Parts Arena all the info is there.
By-pass. Closed, Blocked, Missing ????
i have a heat ex if you want to buy it.
Get in The Combustion Chamber and i will help you. Wont post gas advice on a public forum
Sent you a PM, Not sure if you have to be friends on here to recieve it.
Out of interest do you have a Water softner. ??
Keep pressing the reset button until the temperature comes back on the display
Check inside the grey cover, Probally bottom immersion leaking
Reguarding the Temp dial spinning, Thats broke so a new control pcb will be required.
Reguarding the hot water issue your cylinder will be...
I will state the obvious..Batterys ???
The temperature pots on the pcb where not lined up properly when pcb was fitted..Take pcb out, Turn pots to max, Turn control knobs to max, slot...
Motorised Valve ???
You will need to descale these at least every 6 months, No new seals will be required, A Wet vac hoover is good at getting all the carp out....
1. Hot Tap dripping
2. Wax Capsule Failing
3. Pump failing
Most likely causes
Would that be the KPI or PKI or IPK whatever they call it thingey. So many engineers carp them selves about these..Me i just go back to sleep.
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