Hi - I have an open vented boiler hot water/heating which runs on a single pipe system and its pumping water into the header tank - Found this by sheer coincidence so no idea how long its been like this. It pumps exactly the volume that it then feeds via the pipe at the bottom of the tank - it does not increase the amount in the header tank. Turning just heating on, or just hot water makes no difference - The flow into the header is quite strong, about like a tap half on for instance. The system was drained and refilled several months ago in order to replace a radiator (Nothing wrong with it just shape). I've turned pump down from max 3 to 2 and made no discernible difference. This is in a house with tank in loft and hot water cylinder in bedroom airing cupboard below.
Could this be an airlock or is it likely to be a blockage in feed (if so why does it not overflow the header if its blocked?) - Pump flow faces the 3 port valve - system has worked normally for very many years with current pipe setup and wasn't pumping over previously.
Could this be an airlock or is it likely to be a blockage in feed (if so why does it not overflow the header if its blocked?) - Pump flow faces the 3 port valve - system has worked normally for very many years with current pipe setup and wasn't pumping over previously.
