Replacement Boiler for Boilermate 2000

Hi,

I might be in need of a replacement boiler as it appears my old Myson Apollo 30B is struggling to heat the Boilermate to the required temperature with the demands of the radiators in this cold weather.

I have added some bigger radiators over the last few years, with a recent loft conversion added another. The return from this radiator in the loft is freezing, so I'm going to try some thicker insulation.

Anyway, the Boilermate is working fine and I like the hot water pressure, its only 6 years old and appears to have been well looked after.

If I was going to replace my boiler, what is recommended? We have the BM185 (150L tank), 14 radiator panels (3 double panel, 4 single panel, 4 smal single panel).

Any help appreciated

Would think a boiler of at least 60,000 btu's