How often should one drain the central heating system and refill, adding fresh water & inhibitor?
Or is just adding more inhibitor OK or even needed?
I changed a radiator a while ago, and the water in the old one was very clean, the system has not had anything added or removed for about 10 years.
I went round and bled the radiators a few days ago (Haven't done this in probably 10 years, none of the radiators had gas in it.
Should I worry that it is all about to fall to bits if I don't do anything!?
Thanks :-)