AAON RN-140 - Manual (Page 83)

83
Electric Heating Operation
When a call for heating (G and W1, W2,
etc.) is made the supply blower motors and
electric resistance heaters will energize.
Heating
is accomplished by passing
electrical current through a specified amount
of resistance heaters which will produce the
required heat.
On a fault condition the main limit located
in the supply air or the auxiliary limit
located downstream the supply blower will
remove power from all contactors.
Steam or Hot Water Preheating and
Heating Operation
Valve control for steam and hot water
heating coils are by others. Heating is
accomplished by passing steam or hot water
through the steam or hot water coil
assembly.
Modulating Electric Preheat
Electric preheat is used to temper the
incoming outside air to the unit based on an
enable control signal and outside air
conditions. Electric preheat has a maximum
operation outside air temperature of 60°F
and a maximum preheat discharge air
temperature of 80°F.
Chilled Water or Non-Compressorized
DX Cooling Operation
Controls for chilled water cooling coils and
non-compressorized DX coil are by others.