Can you use twin channel programmer on C plan system?

[Missd99]

Thank you so much guys!
Will get controller on order and update you when complete!
Thanks again

 

[D_Hailsham]

How will I know about checking if when closed it blocking path? I will have to wait if it involves going into loft as my leg is in plaster!!!

You need to trace the path of the vent pipe back to the boiler. If the path goes through the valve, you're in trouble.

 

[Missd99]

Oh yes, the vent pipe!
Well the job will have to wait a few weeks until my cast is off (ladders tricky with one leg lol)! Unless I can find a victim, er I mean volunteer to help.
Thanks again