I've been sizing up my system requirements for a combi boiler, looking at how many rads I will need, replacing singles with doubles etc, being sure that the combi boiler is of a large enough kW to cope. Whilst reading a few topics on this site I've come across the occasional problem of the expansion vessel in the combi being too small for the volume of water in the rads, and the system losing pressure as water is expelled out the prv.
I thought I just had to look at BTUs/Watts and tally up all the radiators then make sure the boiler was big enough to cope. Surely this is linked to the size of the expansion vessel, but obviously not if people are having problems with the expansion vessel being too small for a system. Am I missing something here?
I thought I just had to look at BTUs/Watts and tally up all the radiators then make sure the boiler was big enough to cope. Surely this is linked to the size of the expansion vessel, but obviously not if people are having problems with the expansion vessel being too small for a system. Am I missing something here?