A.O. Smith 28 30 50 60, Installation & Service Manual

Page: 52 / 96

Starting up and shutting down
52 Instruction Manual BFC
7
gis
5. After a number of seconds pre-glow, the gas control is opened and ignition
takes place.
-
The
G
icon is activated.
- The message
IGNITION
appears.
6. After ignition, the flame is detected and the appliance will be running. This
means that actual heating has started. The rotation speed of the fan then
increases to the normal running speed, and the pressure switch will close:
-
The
O
icon is dimmed.
- The
V
and
D
icons are activated.
- The message
RUNNING
appears.
7. Once the water is up to temperature, the heat demand drops off, and the
post-purge starts. This lasts about 25 seconds.
-
The
W
,
G
and
V
icons are dimmed.
- The
S
icon is activated.
- The message
POST PURGE
appears.
8. Following the post-purge, the fan stops and the pressure switch opens:
- The
D
and
S
icons are dimmed.
- The message
POST PURGE
disappears.
At the first subsequent heat demand, the heating cycle will resume from step 1.
ON Ê Ê Ê
13:45 Thursday 63ÉC
Tset 65ÉC
IGNITION
Figure 7.12 Ignition
ON Ê Ê Ê Ê
13:45 Thursday 63ÉC
Tset 65ÉC
RUNNING
Figure 7.13 Running
ON Ê Ê
13:45 Thursday 65ÉC
Tset 65ÉC
POST PURGE
Figure 7.14 Post-purge
ON
14:05 Thursday 65ÉC
Figure 7.15 Running