A.O. Smith THRU 800, Руководство по обслуживанию

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10 Servicing should only be performed by a Quali fi ed Service Technician
OPERATION TOUCH SCREEN DISPLAY
If fl ame is not detected after the sparking ends
(approximately 5 seconds), the control will perform
a postpurge, then start another prepurge cycle
and try to light the burner again. On the 500 and
larger models, the control will lock out if this second
attempt fails. On the 400 and smaller models, the
control will perform a total of 4 attempts before
locking out.
If fl ame is detected, it holds the fi ring rate steady
for a few seconds to let the fl ame stabilize, then it
begins to modulate the fi ring rate based on a set
point or some other command (such as a 0-10V
BMS signal).
Once the call for heat is satis fi ed, the control will
de-energize the gas valve. The blower will continue
to run for approximately 12 seconds during the
postpurge.
The water heater pump will continue to run for its
respective pump delay time before turning off. A 60
second short cycle period will start, which will delay
any new call for heat until it times out.
In Standby, ready to start a new cycle.
Table 1. Sequence Of Operation (Continued.)
Tank Temperature 90°F
Operating Setpoint 93°F
S t a t u s : P o s t - P u r g e
HELP DISABLE
A. O. Smith XP
MENU
Tank Temperature 92°F
Operating Setpoint 93°F
S t a t u s : S h o r t C y c l i n g
HELP DISABLE
A. O. Smith XP
MENU
Tank Temperature 92°F
Operating Setpoint 93°F
S t a t u s : S t a n d b y
HELP DISABLE
A. O. Smith XP
MENU
Tank Temperature 90°F
Operating Setpoint 93°F
S t a t u s : P o s t - P u r g e
HELP DISABLE
A. O. Smith XP
MENU
Tank Temperature 90°F
Operating Setpoint 93°F
S t a t u s : H e a t i n g
HELP DISABLE
A. O. Smith XP
MENU
OFF
GAS
O
N