User Guide

1 Service (continued)
15
Freeze Protection Burner Differential
Once the burner has started firing due to a low inlet temperature,
the inlet temperature must increase by this amount before the
burner turns back off. The installer can adjust this differential
by accessing the Freeze Protection Burner Differential parameter.
The minimum setting is 0°F, and the maximum is 20°F. The
default setting is 5°F (2.8°C).
DHW Settings
DHW Tank Set Point
By installing a tank sensor, the SMART SYSTEM control can
perform the tank thermostat function. The SMART SYSTEM
control automatically detects the presence of this sensor, and
generates a DHW call for heat when the tank temperature drops
below the tank set point differential (Tank Set point Differential
parameter), and finishes the call for heat when the tank
temperature reaches tank set point + offset. This set point will
be applied to the inlet sensor when a tank sensor is not installed.
This parameter can be changed by the installer by accessing the
DHW Tank Set point parameter. The temperature range of this
parameter tank minimum set point to tank maximum set point.
The default value is 125°F (52°C).
Tank Set Point Offset
The tank set point offset measures how far the actual temperature
must go above the set point before the call for heat ends (the
water heater will turn off). This parameter can be changed by
the installer by accessing the Tank Set Point Offset parameter.
Tank Set Point Differential
The tank temperature must drop this amount below the tank set
point (DHW Tank Set point parameter) before the water heater
turns back on. The installer can adjust this setting by accessing
the Tank Set point Differential parameter. The minimum setting
is 0° (0°C), and the maximum is 40°F (22°C). The default setting
is 6°F (3°C).
Tank Minimum Set Point
This setting controls the minimum tank set point for the tank
temperature. The installer can adjust this by accessing the Tank
Minimum Set point parameter. The minimum setting is 60°F
(16°C) and the maximum setting is the maximum tank set point
(Tank Maximum Set point parameter). The default value is 60°
(16°C).
Tank Maximum Set Point
This setting controls the maximum tank set point for the tank
temperature. The installer can adjust this by accessing the Tank
Maximum Set point parameter. The minimum setting is the
minimum tank set point (Tank Minimum Set point parameter)
and the maximum setting is 190°F (88°C). The default value is
140°F (60°C).
To save any changes and return to the Home Screen, press the
RIGHT SELECT [HOME] key. To return to the Status Screen
without saving the changes, press the LEFT SELECT [EXIT] key.
Display Timeout
This is the time for which the display remains illuminated. The
range is 10 seconds to 10 minutes. The default is 3 minutes.
Data Logging
Reset log errors
The reset log errors function clears the last 10 errors log.
Functions
Service Mode Delay
By pressing the pin button on the front of the display for five
(5) seconds, the control will be placed in Service Mode. This
will override all other heat demands. The Service Mode allows
the installer to set the unit to any firing rate for the purpose of
combustion analysis. The delay sets the length of time the water
heater will stay in the Service Mode if no keys have been pressed
before going back to its previous state. This parameter can only
be changed by the installer by accessing the Service Mode Delay
parameter. The time range of this parameter is 1 to 10 minutes.
The default value is 10 minutes.
Freeze Protection Pump On
The SMART SYSTEM control will turn on the water heater and
system pump outputs whenever the inlet temperature drops
below this setting. This is done to prevent the water in the heat
exchanger from freezing. Certain low-temperature applications
(such as snow melt) can operate at temperatures around freezing,
so this setting needs to be lowered in these cases. The installer
can adjust the temperature at which the pump outputs are
turned on by accessing Freeze Protection Pump On parameter.
The minimum setting is -3°F (-19°C), and the maximum setting
is 45°F (7.2°C). The default setting is 45°F (7.2°C).
Service Manual
NOTICE
Never put the Freeze Protection Pump on
a setting lower than the Freeze Protection
Burner On setting.
Freeze Protection Burner On
If running the pumps does not prevent the inlet temperature
from falling closer to freezing, the SMART SYSTEM control
will fire the burner at low fire. The installer can adjust the
temperature at which the burner fires by adjusting the Freeze
Protection Burner On parameter. The minimum setting is -3°F
(-19°C), and the maximum setting is 45°F (7.2°C). The default
setting is 37°F (2.8°C).