Central Heating High Pressure

[tali1]

I cannot set my hot water and radiators more than 50 C on my central heating boiler .Anything over that and that pressure starts going into red and over 2 bar.I can have the central heating on for 10 hrs or more and the room temprature doesn't even go past 20C(i know this is room temp but it should go past that).
I switched it off and flushed the system but the problem is still there.I have bled all the radiators regularly - they have no air locks whatsoever.
This is first time i have used central heating intensively since last winter.However that time there was a constant droning noise -which isn't there anymore.
Also i opened up the boiler cover and several of the pipes are wet -i cannot locate if it is a leak or condensation

[The Builder]

Nothing to do with the rad system, I'm afraid, tali.

It does sound as though something has sprung a leak. Your problems could well be caused by electrical sensors, or even the circuit board short circuiting.

Time to call out the cavalry ;o(

[ivor4781]

heat exchanger has gone

[tali1]

Seems i didn't do a proper (cold, switch it all off ) radiator bleed.This seems to have cured the problem as there was actually a lot of air in the upstairs radiators!

[Dogsbody2]

Your description of the problem is not matched by your identified solution.
Expect that the root cause is more complex and costly to solve than this.

[tali1]

Well, all seems fine( re-read the bleed reply) -with pressure fine.Loft and rear bedroom radiators are the ones that have to have a little air bled daily.