My Keston C36 combi boiler is acting up - the water's getting way too hot.
It's hitting around 90 degrees when in use. And then bounces back to 40s. The led indicator for DHW also turns ON/OFF while temperatures bounces. (PFA)
Any ideas what might be causing this or how I can fix it?
To add...
This error code appears daily when the shower is in use in main bathroom (and abruptly stops hot water)
It works fine if I use shower in second (ensuite) bathroom.
On the website it says "E03: Overheated boiler".
(It might be true as the water in main bathroom comes out real hot! Even if I...