
Fully Pumped Heating System using SRT323 room
stat, cylinder stat and Two (2 Port) Spring Return
Valves with auxiliary switches and a Secure
SHP021 / SHP027 electronic programmer.
This diagram is schematic and should be used for
guidance only.
18
1
2
3
4
5
6
L
N
MAINS
SUPPLY
E
N
4
FROST
STAT IF
FITTED
CYL
STAT
PUMP &
BOILER
L
N
1
SRT323
ROOM
STAT
L
ZONE
VALVE
ZONE
VALVE