My boiler (BG Potterton Precision) will soon reach its end of life. Rather than being left in the lurch when it does, I've been analysing my present CH system so I can better make a decision on a replacement system when the time comes (e.g. boiler capacity or even replacement by ASHP). The property was built in 1990 and originally had a non-condensing boiler (although I suspect it had weather compensation - or maybe it was just a frost-stat). From my heat loss analysis, the radiators are under-sized. The original boiler was replaced with a condensing boiler around 10 years ago. It doesn't seem to have been down-rated and I suspect the flow temperature would have been set lower than on the original, so aggravating the under-sized radiator situation.
I have been monitoring the flow and return temperatures and have today tried to lower the flow temperature slightly to see the effect. The flow-return temperature differential remained much the same at around 17°C. Although I can record these temperatures, I can only deduce from the sounds coming from the boiler that it is modulating - I have no way of recording any objective data. Although the boiler is not cycling rapidly, it does cycle several times per hour. Is this normal?
I attach a graph of the flow and return temperatures. Does this look normal? The boiler doesn't seem to attempt much in the way of modulation. Why does the temperature increase rapidly before the boiler cuts out? Can any experts here analyse what is going on please.
I have been monitoring the flow and return temperatures and have today tried to lower the flow temperature slightly to see the effect. The flow-return temperature differential remained much the same at around 17°C. Although I can record these temperatures, I can only deduce from the sounds coming from the boiler that it is modulating - I have no way of recording any objective data. Although the boiler is not cycling rapidly, it does cycle several times per hour. Is this normal?
I attach a graph of the flow and return temperatures. Does this look normal? The boiler doesn't seem to attempt much in the way of modulation. Why does the temperature increase rapidly before the boiler cuts out? Can any experts here analyse what is going on please.
