059705–00 REV. B
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04
SPACE FEEDBACK
UNDERSTANDING OPERATION CONCEPT
The Genesis Heat-Timer
®
is design to accept space temperature feedback from the 3 space sensors included with the controller.
These sensors are preprogrammed to specifically communicate to the Genesis Heat-Timer
®
control. Additional sensors may be
programmed to the Genesis Heat-Timer
®
control and provide additional space temperature feedback.
Using the web based program ICMS—Internet Control Management System, the user is able to designated a desirable/adjustable
building temperature setting similar to the thermostat setting found in residential heating applications. The data retrieved from the
space sensors is then averaged and transmitted to the Genesis Heat-Timer
®
control. The Genesis Heat-Timer
®
control then uses
this data to determine what, if any, changes are required to the outdoor reset setting currently being used. This space temperature
feedback is available for both steam and hydronic heating.
SPACE TEMPERATURE FEEDBACK—
HYDRONIC HEATING
In hydronic heating applications, the addition of space temperature feedback is more straightforward to understand. The space
temperature feedback has 2 functions depending on the average space temperature and its relationship to the desired
building temperature.
If the average space temperature exceeds the building target temperature, the Genesis Heat-Timer
®
control will shutdown the boiler
or in a 3-way mixing valve application, close the valve. This will continue until the average space temperature falls below the building
target temperature. The Genesis Heat-Timer
®
program will then adjust the reset ratio accordingly so that the adjusted system
temperature is lower when the boiler or valve is returned to heating function.
If the average space temperature is below the building target temperature, the Genesis Heat-Timer
®
program will recognize this and
automatically adjust the outdoor reset ratio to increase the system water temperature.
This self learning logic of the Genesis Heat-Timer
®
allows the installer to select a random ratio setting and allow the program logic to
adjust accordingly without worrying about the tenant comfortable level being compromised.
SPACE TEMPERATURE FEEDBACK—
STEAM HEATING
In addition to the various stages of the Steam Cycle as detailed in the previous section, the Space Temperature Feedback adds
another layer to the OFF portion of the cycle. At the end of the OFF cycle the Genesis Heat-Timer
®
control looks at the Heating
System sensor to see if the system temperature has dropped below the System Set point minus the adjustable differential before it
begins a new heating cycle. This period is referred to as Thermal Lockout. With Space Sensor feedback, the Genesis Heat-Timer
®
control also looks at the desired building temperature setting and compares that setting with the current average space temperature.
If the average measured space temperature is above the target building temperature, the Genesis Heat-Timer
®
control will delay
starting a new heating cycle. This will occur even if the system sensor temperature has fallen below the differential setting that would
normally start a new heating cycle. This period is referred to as Space Lockout.
Through the logic of the Genesis Heat-Timer
®
program, depending on whether the average building temperature is above or
below the desired building target temperature, the heating setting will automatically adjust accordingly. This self-learning concept
of the Genesis Heat-Timer
®
ensures the heating of the building matches the changing outdoor temperatures and the heat loss of
the building.
