General Operation
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IM-HC 561174 1120 Basic Heating Control
3.4 Control Features
The Basic Heating Control calculates a mixing supply water temperature
based on the outdoor air temperature. The Basic Heating Control uses a
heating curve and optional indoor temperature feedback from an indoor
sensor in this calculation.
3.4.1 Outdoor Reset
3.4.2 Floating Action
A 24V AC floating action actuator motor is connected directly to the
Basic Heating Control on the COM, OPN, and CLS terminals (7, 8, and 9).
The Basic Heating Control pulses the actuator motor open or closed
to maintain the correct mixed supply water temperature at the supply
sensor. The valve that the actuator is connected to can be either an
injection valve (on the Injection Station), a mixing valve, or a diverting
valve. A visual indication as to whether the control is currently opening or
closing the mixing valve is displayed in the LCD.
3.4.3 Warm Weather Shut Down (WWSD)
The Basic Heating Control monitors the outdoor temperature and shuts
off the heating system seasonally when outdoor temperatures exceed the
Warm Weather Shut Down setting. This reduces energy use during the
summer when the heating system is not needed and saves wear on system
components.
3.4.4 Exercising
The Basic Heating Control has a built-in exercising function. If the system
pump or valve has not been operated at least once every three days, the
control turns on the output for a minimum of 10 seconds. This minimizes
the possibility of a circulator pump or valve seizing during a long period of
inactivity. The Basic Heating Control ensures that the mixing valve operates
over its entire range at least once each exercising period. While the control
is exercising, the Test LED flashes.
The exercising function does not work if power to the
control, circulator, or valve is disconnected.
Summary of Contents for IM-HC 561174 1120
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