Hi, I have an open fire with back boiler that does my hot water and radiators. The house was built in the early 1900s with a solid front wall (no cavity) so heat loss in the house is bad even with double gaglazing etc. It currently has 5 radiators in the house that are all ancient single panel type of various sizes with the biggest being about 1600x600. I want to replace the 2 large radiators with new double convector type one's but I don't know if my set up will heat them effectively? I have now idea on the size of the back boiler as its hidden away nor do I know the pump size as that is also hidden away. Can anyone help? Or do I need to start digging out my wall to find out the pump and boiler specs? 😨