DISCHARGE AIR/WATER SYSTEM
The 9100 Series heating systems can be used as straight hydronic heating appliances or as a combination
hydronic and forced air system with the addition of a field supplied air handler, water coil, and duct
sensor. In all systems, to deliver stored heat, the 9100 Series needs to receive a signal from a thermostat,
BACnet system, energy management system, or serial communication input. This signal will initiate one
of several levels of heat call.
When a heat call is initiated, the system displays the type of heat call on the status screen of the control
panel, the primary loop pump is energized, and the outlet water temperature is monitored. The desired
discharge water temperature is regulated based off of the target temperature (L127) established.
BRICK CORE CHARGE CONTROL
Steffes heating systems are capable of providing a wide variety of heating options for various
applications. The heating system's primary function is to store energy in the form of heat. Because the
system is operated with microprocessor based control, it is very flexible in meeting the demands of the
application. The rate at which energy is stored can be controlled with BACnet, 4-20, or pulse inputs.
The amount of energy stored is based on the target level which is determined by outdoor temperature,
utility peak conditions, building automation system, and/or the heating requirements. Sensors monitor
the brick core temperature and communicate this information to the processor control board. If the
current charge level is lower than the target level of any core, elements will be energized as allowed by
the load management system. As the brick core approaches the desired temperature, the integrated SSR
control adjusts the charging rate of the brick core, optimizing the element life.
CHARGE CONTROL OVERRIDE
If desired, the ThermElect Hydronic system can be programmed to allow a charge control override. This
override allows the user to force the system to target a full core charge level and can be initiated or
canceled at any time. If an override is initiated, the system targets a full core charge level during the next
off-peak period. It continues to charge during off-peak hours until it achieves full (maximum) core charge
or until the override is canceled. Once full charge is achieved or the override is canceled, the system
charges according to the standard configuration.
MAINTENANCE AND CLEANING
Steffes recommends conducting an annual system check-out as described on Page A.09.
TURNING SYSTEM “OFF” AND “ON”
The system is fully automatic and does not need to be manually disabled. Talk to your installer or energy
management person for additional information.
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