Gloworm 24ci problem

[Meurig]

Hi guys,
Our boiler has started not heating water consistently. The symptoms are:

1- Water will run hot, then cold then hot. It seems to cut off briefly but sometimes it wont run hot.

2- The central heating appears to work but i believe it does cut out briefly as well but doesn't cut out long enough to cool down.

3- The digital display on the boiler will read the temperature but will switch to show 8.8 bar briefly. The cut out seems to coincide with this switch from temp to displaying 8.8 bar.

4- It occasionally (once or twice) shows an F9 fault. According to the manual this is described as a "Water Pressure Sensor Fault". The "possible cause" is "faulty sensor connection, check wiring".

Does anyone have any idea what could be causing this and is it something that a competent DIY'r can fix?

The boiler is out of warranty and foolishly I have no maintenance plan to call upon.

Any help would be appreciated.

 

[twgas]

From the info you've given I would suspect your system needs a good clean.
Hot/cold/hot/cold is classic case of blocked plate, faulty pressure sensing, you will NOT have 8.8bar, = dirty system

 

[Meurig]

Cheers for the reply.

Is there any guidance as to how to proceed or is it a case of get the professionals out?

Thanks

 

[twgas]

Depends on your skill, confidence and competence.
Easiest, though possibly not the most successful is to add a cleaner.