Hobson's Choice

[Tommyrot]

Hi folks,

I’m facing an issue and I’d appreciate your help. I have a conventional (gravity fed) central heating system with a water tank in the loft, a hot water cylinder and a diverter valve in an airing cupboard. My issue concerns my bathroom radiator and when it gets hot. It’s like this:

HW only = bathroom rad (hot) [tap water gets hot]
CH only = house rads (hot), bathroom rad (cold) [*tap water unaffected] [*as to be expected]
HW+CH = house rads (hot), bathroom rad (cold) [tap water gets hot]
(From this I conclude that the diverter valve is working OK.)

Until yesterday, the bathroom radiator remained cold even with the HW only. Then (on a whim) I went round all the active radiators and balanced all the lockshield (flow) valves to a quarter turn. Hey presto, the bathroom radiator became hot with the HW only. It surprised me that this re-balancing made any difference to the bathroom radiator. The taps are fed from the hot water cylinder, so the supply to the bathroom rad must be shared by the other radiators. By the fact that the tap water is hot when the CH and HW are on, I can only think that the bathroom rad is being starved of hot water.

In any case, the bathroom rad should also get hot when both HW+CH are on, but it doesn’t. It used to get hot. It doesn’t have a TRV, but both valves are open.

What would you suggest?

Thank you. Your help is much appreciated.

(This forum text editor must be the only one I've seen which allows you to add a gallery, table and code, but not a bulleted or numbered list!)

 

[CBW]

(This forum text editor must be the only one I've seen which allows you to add a gallery, table and code, but not a bulleted or numbered list!)

Actually, it used to incorporate these, but since they “upgraded“ the forum, they seem to have disappeared, I did mention it to the admin, but perhaps still working on it?

Anyway, your issue: it seems to me that the bathroom radiator only gets hot on a hot water demand, so likely the plumbing arrangement. Forget about the running hot water as you don’t have a Combi Boiler. It might be that you need to call someone out, as often this needs eyes on site.