On 15/05/2021 02:05, John Rumm wrote:

Yup, I know someone with one of those and a gravity circulation loop...



There are still Baxi Bermuda gas back boilers with the radiant fire
fixed to the front. One neighbour close by still uses his. That
has 28mm gravity feed to the hot tank and 22mm pumped rads,
with 4 tapped cores in the side of the Hx. House was built 1976