In article .com,
kiich wrote:
whats the round object that i cant figure out??? cant be power as thats
coming from the main power socket withte fuse right?

i haven't opened the round object yet - could it be the line from the
room thermostat??

Likely.

With the system all switched on - ie heating and hot water - turning down
the cylinder stat (you should hear it click) while the room one is higher
than ambient temp should force the motorised valve to the heating
position, and you should hear this happening.

They're normally wired for hot water priority, so if both stats are
calling for heat, the water one wins.

--
*A 'jiffy' is an actual unit of time for 1/100th of a second.

Dave Plowman London SW
To e-mail, change noise into sound.