u/Friendly_Brain7352

36kw Worcester Bosch boiler, brand new install but with ancient rads. installer did a flush and left it flushing for about 10 days occasionally clearing the filters. No issues at all with the install (brilliant service would recommend to anyone) but wondering about the effectiveness of the old rads. 1930s granite house, next to no insulation. Roughly 30% poorly insulated flat roof extension. Flow temp set at 65⁰. 160 SQM house mostly empty as still renovating, hive thermostat set at 20⁰ but still feels cold. Previously used to 100sqm cottage and felt cosy with stat at 18⁰

Cheers for your input