"Stuart Black" wrote in
:


Today (Sunday) the hot water is refusing to heat up.

I figured there might be air in the system and found a little screw on
the infeed from the boiler to the hot water tank. I loosened this
temporarily and some air came out followed by a small amount of water,
but the pipe to the hot water tank is still not getting hot so the
water inside the tank is not getting hot.

I checked the CH expansion tank and that is OK, i.e. it hasn't run out
of water, it seems to fill OK when the level drops.

Any ideas what else i should look at ?

It sounds as if your boiler and pump are not working; I know it seems a
bit obvious, but you don't say, and it's hard to see how they can be
with your description, also if the C/H is working, which again sounds
impossible, given your description, as three port systems are generally
HW priority.

The bleed valve you operated gets air out of the primary (boiler/hot
water coil) circuit, which appears to be ok

Try putting your valve in the "manual" position; this should enable the
pump and boiler to operate.

And repost, addressing my points, so the real experts have a bit more to
go on

HTH

mike