User’s Information Manual
4SMART SYSTEM control module
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 to 190°F. The default value is 180°F.
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.
F: Outdoor air reset
Outdoor air shutdown
When the outdoor air shutdown rises above this point, the control will block all SH demands (DHW demands will still be active). This parameter can be changed by the user or the installer by accessing parameter F5. The temperature range of this parameter is 0°F to 120°F. The default value is 80°F.
Outdoor air shutdown differential
The outdoor air shutdown differential parameter is the number of degrees below parameter F5 the outdoor air temperature must go before the boiler will respond to a SH demand. This parameter can be changed by the user or the installer by accessing parameter F6. The temperature range of this parameter is 0°F to 90°F. The default value is 10°F.
Boost temperature
If a SH demand lasts longer than the programmed time delay setting and there have been no DHW demands, the control will increase the water temperature set point by the amount in this parameter. If the SH demand continues through another time period, the set point will be increased again. This will continue until either the SH demand ends, a maximum of 20 increases has occurred, or the maximum set point has been reached. Once the SH demand has been satisfied the set point will revert back to its calculated setting. The boost temperature can be changed by the installer by accessing parameter F8. The temperature range of this parameter is 0°F to 45°F. The default value is 0°F. This feature will be active if this parameter is set to anything other than 0°F.
Boost time
The boost time parameter sets the amount of time that must elapse with a SH demand before the water temperature set point will be increased. This parameter can be changed by the installer by accessing parameter F9. The time range for this parameter is 1 minute to 60 minutes. The default value is 20 minutes.
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