AAON V3-E - Manual (Page 26)

26
Table 3 - Drain Trap Dimensions
Draw-Through
Drain Pan Pressure Trap Dimensions
Negative Static X X/2
(inches of water) (inch) (inch)
-0.50 1.50 0.75
-1.00 2.00 1.00
-1.50 2.50 1.25
-2.00 3.00 1.50
-2.50 3.50 1.75
-3.00 4.00 2.00
-3.50 4.50 2.25
-4.00 5.00 2.50
Heating Coils
One or two row hot water and steam heating
and preheating coils can be factory installed.
All valve controls for heating coil operation
are field supplied and field installed.
Water coils should not be subjected to
entering air temperatures below 38°F to
prevent coil freeze-up. If air temperature
across the coil is going to be below this
value, use a glycol solution to match the
coldest air expected.
Chilled Water Coil
Factory installed four, six or eight row
chilled water cooling coils can be factory
mounted. All valve controls for the cooling
coil operation are field supplied and field
installed.
Electric Preheat
The modulating electric preheat option is
designed to temper the incoming outside air
to the unit based on an enable control signal
and the outside air conditions.
A 24VAC enable signal must be provided to
the [PHE] terminal to enable the operation
of the electric preheat. Once the preheat
controller is enabled it will monitor the
outside air temperature to determine if any
capacity of preheat is needed. If the outside
air temperature falls below the outside air
temperature setpoint the electric preheat will
be started up and maintain the leaving air
temperature setpoint with
both SCR
controlled and staged electric preheat. Both
setpoints are set with push button LCD
interface on the preheat controller. Outside
air
temperature sensors and preheat
discharge supply air temperature sensors are
factory installed and wired to the preheat
controller. Electric preheat has maximum
operating outside air temperature of 60°F
and a maximum preheat discharge air
temperature of 80°F.
[COM], [PHO] & [PHC] feedback terminals
are provided to communicate if the electric
preheat is in operation. PHO is a normally
open contact, PHC is a normally closed
contact, and COM is the common. These
terminals are not required to be connected.
[PHE] is the electric preheat operation
enable. [PH+] and [PH-] are the preheat set
point reset terminals.
Refrigerant Piping
(See back of the manual for refrigerant
piping diagrams and connection sizes.)
Piping from the condensing unit to the air
handling unit is the responsibility of the
installing contractor.
The
Split System Configurator or
Refrigerant Piping Calculator in
AAONEcat32 should be used to determine
acceptable refrigerant line sizes.
The pipe sizes must be selected to meet the
actual installation conditions and not simply
based on the connection sizes at the
evaporator or condensing unit.