I have a Ravenheat RSF100 ET Combi Boiler. had to strip down to repair water leak. Put back together, Fan works micro switch from diaphram works, replace both thermisters, fires up evertime no problem, water just does not get hot. If anyone has any suggestions how the problem can be solved it would be much appreciated.

Cozzie, November 2011

is the heat exchanger OK?.if it is blocked with scale it makes the flame go up and down and water temp go up and down

A1, November 2011