Worcester Highflow 400 RSF Installation And Servicing Instructions page 15

Fig. 10. Functional flow diagram.
Fig. 11. Room/frost thermostats and programmer.
Room thermostat
Live
Remove link
5 4 3
Frost thermostat
5 4 3
Switched live
Neutral
Connector X13
on control board
2 1
Connector X13
on control board
2 1
Fig. 12. External programmer connections.
To External Programmer
Switched central
heating from
programmer
Switched hot
water from
programmer
Live supply
to programmer
Neutral
Plug-in
connector
15
4
Connector
3
X12 on
control
2
board
1
Note: If programmer fails, link
connector terminals, as shown by
dotted line, to create temporary
heat availability.