059705–00 REV. B
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SETTINGS—ADVANCED HEAT MENU
THERMAL LOCKOUT
Selections:
Off, Auto, Manual
Default:
Auto
Description:
The Thermal Lockout is an energy saving feature that prevents a cycle from
starting when the heating system is hot. When a cycle is over, the pipes and radiators
may still be very warm. Therefore, they continue to heat the ambient air. If more steam
is added during that time, the ambient space will begin to overheat. The Thermal
Lockout prevents this from occurring as it allows the system pipe temperatures to fall
through the Heating System Differential before reactivating the heat source.
The Thermal Lockout should be set to AUTO unless the system dissipates heat very
quickly, as might occur with air handling units.
To adjust the factory default Heating System Differential of 20°F, select MANUAL and
adjust to the desired Heating System Differential setting. The range of the Heating
System Differential is 0°F to 75°F.
The Heating System Differential is the temperature range through which the HSS must fall
below the System Set Point before another cycle can begin. The selected starting value
for the System Differential depends on the value of the System Set Point. The higher the
System Set Point, the higher the Differential value can be set. As an initial setting, set the
heating system to restart at approximately 125°F. At this temperature most of the residual
heat in the radiators has dissipated, but enough heat remains to keep the ambient
temperatures warm during the time it takes the Genesis Heat-Timer
®
to establish heat.
For example, if the System Set Point is 170°F, then set the Heating System Differential
to 45°F, so the Set Point less the Differential is 125°F. If the System Set Point is 140°F,
then set the Differential to 15°F. If the space temperature becomes too cold between
cycles, reduce the amount of the Heating System Differential.
If the building is overheating, especially in mild weather, check the System Set Point.
If the System Set Point setting is correct, then increase the System Differential.
See “System SetPoint” on page 62
Once the Heating System Differential is adjusted to the desired setting, place the
Thermal Lockout setting to AUTO before exiting the menu.
SYSTEM RUN-ON
Selections:
0–360 minutes
Default:
2 minutes
Description:
The System Run-On setting controls the length of time the System
Pump (Output) relay remains energized after the Boiler Output relay turns off.
If the System output is used to control a combustion-air damper, the run-on allows the
damper to bring more fresh air to the room for the next boiler initiation.
THERMAL LOCKOUT
BACK SAVE
Off
Auto
Manual
SYSTEM RUN-ON
BACK SAVE
m
