I've been reading past posts to try to get a feel for which condensing
boilers are currently on the recommended list. However, descriptions
like 'system boiler' and 'heating boiler' seem to have variable meanings.

If I've got it right, a 'heating boiler' has one flow and one return and
any pump(s) must be installed within the piping whereas a 'system
boiler' has two flow and two return, one pair for central heating and
one pair for domestic hot water, both of which have a pump already
installed within the boiler casing.

Anyone care to clarify/correct me?

--
F

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