Honeywell CT70 - Manual (Page 8)

8
DEFINITIONS OF TERMINAL FUNCTIONS
Each terminal of the CT70 controls a different heat pump
function. Here is a list of the possible heat pump
functions:
Function Definition
FIRST STG. HEAT: When this terminal is activated, the heat
pump is on and heating the living space.
AUXILIARY HEAT: When this terminal is activated, the
auxiliary heating source is on because the
heat pump is unable to meet the heating
demand of the living space.
FIRST STG. COOL: When this terminal is activated, the heat
pump is on and cooling the living space.
COMPRESSOR: When this terminal is activated, the heat
pump is on and either heating or cooling
the living space, depending on the system
switch position.
C/O VALVE HEAT: Heating Changeover Valve. This terminal
is activated when the system switch is in
the HEAT position. It provides changeover
in heat pumps that change over in
heating.
C/O VALVE COOL: Cooling Changeover Valve. This terminal
is activated when the system switch is in
the COOL position. It provides
changeover in heat pumps that change
over in cooling.
EM. HEAT: Emergency Heat. This terminal is
activated when the system switch is in the
EM. HT position. In this situation, the heat
pump is not activated.