I have a sealed system with an expansion vessel under boiler in a Halstead System Pod (vessel, pump pressure relief valve etc).
Boiler is making banging noises so I though that I would flush out, use cleaner, flush again and then use inhibitor. I have managed to put the cleaner in and heating is now back on, but I have a couple of questions before I do the next flush.
Q1. Today, I used a drain valve on low point of pipework and just let the system empty into a drain via hosepipe. I opened bleed valves in all rads and flushed system for 10 mins with fill loop, then closed drain valve & used towel rad to insert cleaner & finally filled system. Is this all I need to do or do I have to remove CH pump to flush system properly? How long do I have to flush system via fill loop, before closing drain valve?
I think my towel rad (highest rad) is acting as the expansion vessel. There is a cold part at top which seems to get smaller when system heats up. The expansion vessel (1.5 bar) has a metal braid pipe which is always cold and the guage showed 2.0 bar when the system was hot. I thought hat the braid should be hot especially when system was up to 2.0 bar? Is there any way this braid could be blocked to prevent the vessel from doing its job? Does anyone know how I can check the exp vessel is operating correctly?
thanks in advance