User manual

DHW FUNCTION
DHW FUNCTION
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR 12i System/24i System
8 716 107 375b (11/05)
56
FAULT FINDING
& DIAGRAMS
Wait
5 seconds
IGNITION
SEQUENCE
(see detail)
NO
YES
POWER
SWITCH
ON
Diverter valve
in DHW
position
Pump ON.
BLUE
LIGHT
ON
BURNER
LIT?
Fan to
start
speed.
Stop spark.
Wait
10 seconds
5th
attempt?
LOCKOUT
Fan (& gas)
modulation
to achieve
set
temperature
(75°C)
DEMAND
END
Gas valve
OFF
Pump run 3
minutes
Fan run 30
seconds
Over temperature shut-
down if water tempera-
ture is 8°C above set
value.
Gas valve OFF.
Spark
ignition
4 seconds
NO
YES
Cylinder stat
calling
AND
Facia
mounted
programmer
ON
DOMESTIC
HOT
WATER
DEMAND
GREEN
FLAME
LIGHT
ON
Burner shut down if
primary temperature
94°C
(until 84°C)
IGNITION SEQUENCE
RETURN TO THE MAIN
INSTRUCTIONS PAGE 57 FOR
PROTECTION FUNCTION.