had a new condensing boiler fitted last march, and all has been well.... Now its the boilers first winter and its starting to get cold, i am unsure if its working right. Its normally set to 'e' on the boiler temp, and when the boiler comes on, it works OK until it first shuts down, and then it only fires for approx 30secs, then shuts down, when its cycling. The thermostatic readout tells me its calling for heat, but the boiler is circulating or switched off. This happens when it gets to within a degree of the set temp. Also when it does this, the rads never seem to get very warm, as the boiler is switching off. It does this cycling every 15mins or so. I am unsure if I should be setting the boiler to Max, now its getting cold (never had a condensing one before). Should I be calling the installer back, or is this how they are supposed to work..... Ambient temp in the house is generally around 19degrees. Would welcome any advice from the experts......