1Service
SH Differential
The SH differential sets how many degrees below the turn off temperature the temperature has to go before the boiler will turn on. This parameter can only be changed by the installer by accessing parameter B5. The temperature range of this parameter is 0°F (0°C) to 54°F (30°C). The default value is 20°F (11°C).
C: Data logging
Hours running SH
The hours running SH parameter shows the total number of hours the boiler has been in the SH firing position. This parameter can be viewed by the user and the installer by accessing parameter C1.
Hours running DHW
The hours running DHW parameter shows the total number of hours the boiler has been in the DHW firing position. This parameter can be viewed by the user and the installer by accessing parameter C2.
Ignition attempts
The ignition attempts parameter shows the total number of times the boiler has attempted to fire. This parameter can be viewed by the user and the installer by accessing parameter C3.
Show last 10 errors
The control will log the 10 most current errors with the date and time the error occurred. This parameter can be viewed by the user and the installer by accessing parameter C4.
D: Functions
Reset last 10 errors
The reset last 10 errors parameter allows the error counter to be reset to 0. This parameter can only be cleared by the installer by accessing parameter D1. Once accessed, press the RESET key to clear the counter.
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 either maximum firing rate or minimum firing rate for the purpose of combustion analysis. The delay sets the length of time the boiler will stay in the Service Mode if no keys have been pressed before going back to its original state. This parameter can only be changed by the installer by accessing parameter D2. The time range of this parameter is 0 to 40 minutes. The default value is 20 minutes.
Service Manual
E: DHW settings
DHW boiler set point
When a DHW call for heat becomes active, the control will use the DHW boiler set point to determine the firing rate of the boiler based on the actual water temperature. This parameter can be changed by the installer by accessing parameter E1. The temperature range of this parameter is 50°F (10°C) to 190°F (88°C). The default value is 180°F (82°C).
SH/DHW switching time
The SH/DHW switching time parameter sets the length of time the control will stay in DHW Mode when a SH call has been received. After this time period has expired the control will revert to SH Mode. If a DHW call is still active the timer will reset. After the time period has expired the control will revert back to DHW Mode. This will continue until one of the demands has been satisfied. This parameter can be changed by the installer by accessing parameter E2. The time range of this parameter is 10 minutes to 240 minutes. The default value is 30 minutes.
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 6°F (3.5°C) below the tank set point, and finishes the call for heat when the tank temperature goes 4°F (2°C) above the tank set point. This parameter can be changed by the installer by accessing parameter E3. The temperature range of this parameter is 32°F (0°C) to 212°F (100°C). The default value is 125°F (52°C).
F: Outdoor air reset
Outdoor air reset operation
If an outdoor air sensor is installed, the control will calculate the water temperature set point based on the outdoor air temperature. As the outdoor air temperature drops the water temperature set point increases. This feature allows the boiler to be more efficient in periods of mild weather, see FIG.
Minimum air temperature
When the outdoor air temperature drops below this point, the water temperature will be at its maximum setting (FIG.
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