Should I Replace Only the Boiler or the Entire Heating System?

[epipeinfo]

Hi,

I'm planning to replace a back boiler (which is at least 15 years old) with a combi boiler. Assuming that the rest of the system is the same age, is it sufficient to flush the existing radiators and pipes, or is it better to replace the radiators and pipework as well?

Duraflow | Leaky Pipes

 

[Danger]

Welcome to PF, Epipeinfo.
Your terms confuse me, as to what "back" and "combi" mean, but that's irrelevant to the rest of the question. Someone more knowledgeable will appear shortly. Meanwhile, my thought is that if there won't be significant changes in pressure, flow rate, or temperature then a simple flush and an inspection to ensure reliability should be enough. If there will be changes, then the piping and rads might need to be upgraded to meet the new requirements. This is far beyond my ability to advise upon.