hello ... i seem to be having problems with the three port valve on my central heating system its a honeywell i changed the head motor today because it wasn't switching to ch but still no joy they dont seem to be any power to the motor . but i dont know where the power comes from timer / room stat ect . the timer i have is a acl switchmaster sm400 .manualy moving the lever to ch works ok but with the motor out of the head the cog dont move .