Hot & cold bar shower

[stegra]

1 hour ago, jddevel said:

I know this topic is now a few days old but I remembered a problem yesterday regarding hot water flow (admittedly in a house) that occurred years ago in the days of immersion tanks rather than combi boilers. As a result of air building up in a "T" off for draining purposes of the hot water circuit from the immersion tank it created a "air valve" which by its presence restricted the flow.

It might be that the Tee was put there to bleed the air out of an air lock the gravity system. I had to add a branch at a high point recently to do that. A far riskier way is connect a hose between a hot and cold tap or block a mixer tap with your hand whilst giving short bursts on the cold to force the air back to the cylinder. The danger being that you burst the cylinder with mains pressure. Very much a nerve wracking method of last resort with the potential for calamity.