Steffes 7140 - Manual (Page 7)

Comfort Plus Commercial Hydronic Operation
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Operation
TEMPERATURE CONTROL
Temperature set point is adjusted at the wall thermostat(s) or the main system control. If temperature in the area
drops below the desired set point, a heat call is initiated and the primary loop pump is energized. The variable
speed core blower automatically adjusts speed in relation to brick core temperature to achieve the desired outlet
water temperatures. The heated water is then pumped to the area (zone) from which the call originated.
The versatility of this system allows it to fit many applications. The Comfort Plus Commercial Hydronic is de-
signed for use as either the sole heating source (“stand alone” furnace) or as a supplement to ducted heating
systems such as heat pumps.
The Steffes Air Handler can be interfaced with a standard heat pump system and will provide comfort modula-
tion. The system will monitor the outlet air temperature and modulate in heat from the Comfort Plus Commercial
Hydronic as needed to maintain the desired output air temperature. If one of the zones is a water coil used to
temper duct temperatures, an optional duct sensor (Order Item# 1041536) can be used.
BRICK CORE CHARGE CONTROL
The amount of heat stored in the brick core varies in relation to outdoor temperature, current building load, utility
peak conditions, and/or the heating requirements. The outdoor sensor, if installed, monitors outdoor temperature
and provides this information to the system. As the outdoor temperature decreases, heating requirements increase
and the system stores more heat accordingly.
The amount of heat stored in the system can also be regulated by a signal from a BACnet
control, energy management system, or serial communication input.
CHARGE CONTROL OVERRIDE
If desired, the Comfort Plus Commercial 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 cancelled
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
cancelled. Once full charge is achieved or the override is cancelled, the system charges according to the standard
configuration.
MAINTENANCE AND CLEANING
Any air filter(s) in the system should be replaced on a regular basis to ensure proper operation and to maintain
overall efficiencies. No additional routine maintenance is required.
If utilizing a heat pump or air conditioning system with the Comfort Plus Commercial Hydronic system, the indoor
coil should be cleaned periodically as dirt accumulation may reduce system efficiency. It is important to follow the
manufacturer’s maintenance and cleaning recommendations for these devices.