A.O. Smith 400 Water Heater User Manual


 
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6. Use the UP or DOWN key to select the value you wish to enter.
7. Touch the SELECT key to accept and store the new value.
Operating Differential Setpoints:
Each of the two stages has an independent Operating
Differential setpoint.
OPERATING DIFFERENTIAL SETPOINT
ADJUSTMENT PROCEDURE
Each of the two stages has an independent Operating Differential
Setpoint. The range of these setpoints is from 1 Degree F to 50
Degrees F for all models. Use the following procedure to change
this setpoint:
1. Touch the MENU key.
2. Scroll the ">" with the DOWN key next to USER SETTING
SCREEN.
3. Touch the SELECT key.
4. Scroll the ">" with the DOWN key until it is pointing to OPERATING
DIFFERENTIAL SETPOINT.
5. Touch the SELECT key.
6. Scroll the ">" with the DOWN key until it is pointing to the STAGE
you want.
7. Touch the SELECT KEY.
8. Use the UP and DOWN key to select the value you wish to enter.
9. Touch the SELECT key to accept and store the new value.
Temperature Units:
Temperature can be displayed in either °F or °C units.
Post Circulate Delay Time:
The time circulation pump will stay on after the burner is turned
off. The time in seconds is adjustable with the following values:
45, 90, 180 or continuous. If the continuous value is selected
the pump will remain on at all times and the post circulate state
time will be set at 45 seconds.
Network Address:
This is a unique number assigned to this boiler to differentiate
it from other boilers or water heater on the same A. O. Smith
proprietary network. A valid Network Address can be any number
from 1 to 31. It is set by default to zero, which is an invalid address.
The boiler will not communicate until it is changed to a valid and
unique number. This prevents two units from trying to respond to
the same request from the PC or supervisory network device.
Configuration Settings Screen:
Displays the status of the dipswitches installed on all boards
as described earlier.
Log & System Info Screen:
Displays the following information:
Elapsed hours of operation (Total time system has been
powered up)
Number of running minutes (Number of minutes system has
been in the run mode)
Number of cycles for each stage (Number of times stage has
been in heat mode).
kBtu rating of the boiler (0 to 5750kBtu in 10kBtu increments)
The software revision level of the CCB, and FCB
microcontrollers.
Current Error Screen:
Displays the last error that the system has detected plus a time
stamp of when the error occurred. (The time stamp is based on
the elapsed hours value at the time the error occurred. It is
displayed in hours and minutes. This error remain displayed
as long as it is still valid. When cleared it is moved to the Error
History Screen. The system will automatically jump to this screen
OPERATING SETPOINT ADJUSTMENT PROCEDURE
The system has a standard programmable Operating Setpoint range
of 70 Degrees F to 190 Degrees F for a GW and of 70 Degrees F to
220 Degrees F for a GB for either tank or inlet probe depending on
selection. The user can easily change the Operating Setpoint at any
time by using the following procedure. When any configuration or
setpoint is changed (and the Select key touched), the new value is
IMMEDIATELY saved to non-volatile memory. The factory default
setting is 120 Degrees F.
1. Touch the MENU key.
2. Scroll the ">" with the DOWN key next to the USER SETTING
SCREEN.
3. Touch the SELECT key.
4. Scroll the ">" with the DOWN key until it is pointing to OPERATING
SETPOINT.
5. Touch the SELECT key.
6. Use the UP or DOWN key to select the value you wish to enter.
7. Touch the SELECT key to accept and store the new value.
High Limit:
The outlet temperature probe contains both an ECO switch and
a thermistor for temperature measurement. The sensed outlet
temperature is used for the automatically resettable High Limit
setpoint. If the sensed outlet temperature exceeds the High
Limit setpoint, a "soft lockout" condition will occur and the burner
will be shut off. This fault condition is automatically cleared
when the temperature drops below the high limit setpoint minus
the high limit differential.
AUTO HIGH LIMIT SETPOINT ADJUSTMENT PROCEDURE/
OUTLET TEMP. PROBE
The High Limit setpoint has a range of 90 Degrees F to 210
Degrees F for a GW and a range of 90 Degrees to 235 Degrees F
for a GB. Use the following procedure to change the automatically
resettable High Limit Setpoint:
1. Touch the MENU key.
2. Scroll the ">" with the DOWN key next to USER SETTING
SCREEN.
3. Touch the SELECT key.
4. Scroll the ">" with the DOWN key until it is pointing to HIGH LIMIT
SETPOINT.
5. Touch the SELECT KEY.
6. Use the UP and DOWN key to select the value you wish to enter.
7. Touch the SELECT key to accept and store the new value.
High Limit Differential:
The outlet temperature must be below the automatic High Limit
setpoint minus the High Limit Differential setpoint before a call
for heat can be generated.
HIGH LIMIT DIFFERENTIAL SETPOINT
ADJUSTMENT PROCEDURE
The High Limit Differential Setpoint has a range of 1 Degree F to 50
Degrees F for all models. Use the following procedure to change
the High Limit Differential Setpoint:
1. Touch the MENU key.
2. Scroll the ">" with the down key next to USER SETTING SCREEN.
3. Touch the SELECT key.
4. Scroll the ">" with the DOWN key until it is pointing to HIGH LIMIT
DIFFERENTIAL SETPOINT.
5. Touch the SELECT key.