Air Handler
11
7.3 Maximum Overcurrent Protection (MOP)
Every installation must include an NEC (USA) or CEC (Canada) approved overcurrent
protection device. Also, check with local or state codes for any special regional requirements.
This protection can be in the form of fusing or HACR style circuit breakers.
NOTE:
Fuses or circuit breakers are to be sized larger than the equipment MCA but not to
exceed the MOP.
7.4 Electric Connections-Supply Voltage
USE COPPER CONDUCTORS ONLY
A knockout is provided on the air handler top panel or side to allow for the entry of the supply
voltage conductors. If the knockouts on the cabinet side are used for electrical conduit, an adapter
ring must be used in order to meet UL 1995 safety requirements. An NEC or CEC approved strain
relief is to be used at this entry point.
The wire needs to be sized in accordance with
the “Wire Sizing and MOP” section of this manual.
Air Handler Only (Non-Heater Kit Models)
The power cord connects to L1 and L2 terminal located on the electrical box in the air handler.
Note to grounding well. The power cord adopts appropriately sized solderless connector or other
NEC or CEC approved means. Check the unit wiring diagram attached for reference.
Air Handler with Heater Kits (Non-Circuit Breaker)
The power supply should be connected to the stripped black and red wires on the heater kit.
Air Handler with Heater Kits Containing Circuit Breaker
VAF
d models with a “B” suffix contain a circuit breaker(s). The air handler has a plastic cover
on the access panel that will require either one or both sections to be removed to allow the heater
kit circuit breaker(s) to be installed. See the
VAF
d Installation Instruction for further detail. The air
handler wires and supply wires are installed directly onto the
VAF
d circuit breaker(s) as shown in
the
VAF
d Installation Manual and wiring diagram.
Low Voltage Connections
Several combinations of low voltage schemes are available, depending on the presence of a
heater kit and whether the heater kit is single-stage or multi-stage. The low voltage connections
are determined by whether the outdoor unit is a condenser or heat pump. The 24V-control voltage
connects the air handler to the room thermostat and condenser. Low voltage wiring is to be
copper conductors. A minimum of 18AWG must be used for installations up to 50’ and 16AWG for
installations over 50’. Low voltage wiring can be made through the top of the cabinet or through
either side. See the “Thermostat Wiring” section of this manual
.
