zone valve keeps going to auto

[cuewoz]

my central heating works but only if before it comes on, i go upstairs to the zone valve, and set it to manual. This is the only valve i can find ( new house) and is only 2 port (1 input 1 output).
Every time the heating goes off and the timer comes back on, no heat in radiators, I check the valve and its gone back on its own to auto!

Any help or is the valve broke?

 

[namsag]

It should always fall back to auto position. sounds like new motor required

 

[doitall]

Maybe wired wrong, the motor need a permanent live to work

 

[namsag]

Wrong the motor needs a switched live through clock then cyl/room stat.
The microswitchwithin the valve needs a permenant live (if its used)