A.O. Smith 500 User's Information Manual page 13

• User Settings Screen:
Each setpoint or user setting has either a limited selection of
values, or a limited range of values. The Up/Down keys are
used to change values. After changing an item, the Select
key is pressed to accept the change, or the Menu key is
pressed to reject the change and restore the item to its original
value. The following setpoints can be changed:
Operating Setpoint:
This setpoint sets the base temperature for the control
algorithm.
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. 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.
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.
HIGH LIMIT SETPOINT ADJUSTMENT PROCEDURE
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.
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 on page 9.
• 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)
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