What fresh hell is this? It’s not even a code?! Ideal Isar He30

22 Dec 2018
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United Kingdom

I’m having a real issue with our boiler. We have an old, obviously dying* Ideal Isar HE30 and as far as I understand it the diverter valve has gone and the central heating is cutting out as if at optimum temperature (with flashing indicator) less than three minutes after being turned on. We are surviving with it but now it’s doing something new that I don’t understand and it’s worrying me.

When the hot water is running, the boiler shows “d” but then will flick to a single horizontal line and sometimes will cycle through a range of different shapes on the display panel - none of which actually letter or number codes so I can’t work out what it’s doing. We do have hot water but I’m worrying that it might be something dangerous... any ideas, anyone?

*we are going to replace it as soon as possible in the New Year but haven’t been able to afford it before Christmas


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Most likely a small leak on to the purple wire.

Take off front panel, remove purple wires ( ribbon cable) from control panel on right hand side. Turn boiler back on. It will now run at max temp for heating and hot water. The control panel will be blank but the boiler operates via the heating controller. Should get you over the Xmas period

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