Ecomax boiler problems

[petezahut]

Hi all, I'm a newbie here and was just looking for some simple advice for my elderly father who is terminally ill.
He has a combi boiler, only thing I know about it is its an ecomax and was fitted under the warmfront scheme a few years ago. It has an electronic display with four buttons, one of a flame, one 'i' and a plus and minus either side of a ladder.

I popped in to see him a couple of days ago and his central heating was on. I turned down the thermostat and thought nothing of it.
Went down the next day, thermostat still turned down but rads still really hot so I went to the switch next to the boiler and turned it from constant to off but the rads are still hot.
He gets hot water no problem so I turned down the temp of the rads on the boiler to the summer setting, the rads still stayed hot.
I then turned down the water temp dial on the boiler and the rads cooled down so it looks like the water dial is now working the hot water and the CH.

I bypassed the themostat but that had no effect so it looks like the problem is internal.

I'm quietly confident I can test or replace certain things but would not dream of touching gas. Any ideas to look for before we call out a CORGI man?

Thanks in advance
Pete

 

[Gasguru]

Perhaps the warmstart (comfort) mode is turned on and the diverter valve is letting by.

 

[petezahut]

Thanks for the reply. I know how to turn off the warmstat thing but how do I check the diverter valve and where about is it?
Pete