radiator heating up in hot water mode on y plan

[numbnutsable]

hi have a y plan cenral heating system the mid position valve motor is switching correctly but in hot water mode the bathroom rad is heating up,should the motor seal heating side while calling for hot water?
is the valve goosed or is this normal.

 

[stem]

Has it always been like this?

The reason I ask, is because in the good old days, many solid fuel systems were piped like this, so that the bathroom radiator (or towel rail) was connected to the hot water gravity circuit to act as a method of dissipating excess heat when the rest of the radiators weren't on.

Welcome to the forum, but for future reference, check where you post your question. This one would probably have been answered more quickly and possibly effectively if posted in the plumbing and central heating section, rather than Trade Talk.

 

[numbnutsable]

hi stem thanks for your reply first time on on forum and managed to place question in wrong place sos
the system in in a house that never had solid fuel just moved in so not sure whether it has always operated this way.
am i right in thinking that the mid position valve should close the flow to the heating side when the hot water tank is calling for heat and all rad are turned off,if so and there is a fault with the valve then all rads should warm up?

 

[seco services]

if only the bathroom rad is warming up then i would say its connected to the hw circuit not the heating.

 

[Hugh Jaleak]

Depends how the system is piped up. Sometimes bathroom rads are connected to HW circuit so you can warm towels etc when CH is switched off.

 

[numbnutsable]

but surely if its piped into the hot water then it will not heat up in the heating mode or could it be a cock up on the original installation

 

[seco services]

then its connected as a bypass.
after the pump but before the motorised valve.

 

[kirkgas]

it could be reverse heating when the hot water is on if the installer was lazy fitting the hot water return into the heating return before the bathroom rad retun connection, it should be piped back to the boiler as the last return connection, try this: turn the heating on as normal check which side of the bathroom rad heats first (the flow), then later when the rad has cooled down turn on the hot water and see if the same side of the rad heats (system is piped ok and 3 port valve may be weeping) if the other side of the rad heats from the water then the pipework is probably wrongly connected.

 

[numbnutsable]

hi thanks for all your help,one thing i forgot to mention that when tank is calling for heat the flow pipe on the heating side is heating up dose this mean the valve is faulty and letting water by?
a big thanks to everone for there advice much more helpfull than other forums

 

[numbnutsable]

sorry if offended anybody who has postd advice have not canceld anythanks intentionaly once again thanks to all for thier help