4

Evacuate Refrigerant Tubing and Indoor Coil

CAUTION
!
UNITDAMAGE HAZARD
Failure to follow this caution may result in equipment
damageor improper operation.
Neveruse the system compressoras a vacuum pump.
Refrigeranttubes and indoor coil should be evacuated using the
recommendeddeep vacuum method of500 microns. The alternate
triple evacuation method may be used (see triple evacuatio n
procedurein service manual). Always breaka vacuum with dry
nitrogen.

DeepVacuum Method

The deep vacuum method requires a vacuum pump capableof
pulling a vacuum of 500 micro ns and a vacuum gage capable of
accurately measuring this vacuum depth. Th ed eep vacuum method
is the most positive way of assuring a system is free of air and
liquid water. A tightdry system will hold a vacuum of 1000
micronsafter approximately7 minutes. SeeFig.6.
500
MINUTES
01234567
1000
1500
LEAKIN
SYSTEM
VACUUMTIGHT
TOOW ET
TIGHT
DRYSYSTEM
2000
MICRONS
2500
3000
3500
4000
4500
5000
A95424
A95424
Fig. 6 --D eep Vacuum Graph

Final Tubing Check

IMPORTANT:Check to be certainfactory tubing on both indoor
andoutdoor unit has not shifted during shipment. Ensure tubesare
not rubbing against each other or any sheet metal. Pay close
attentionto feedertubes, makings sure wireties on feeder tubesare
secure and tight.
Be sure field wiring complies with local and natio nal fire, safety,
and electrical codes, and voltage tosystem is within limitsshown
on unit rating plate. Contact lo calp ower company for correction of
improper voltage. See unit rating plate for recommended circuit
protection device.
NOTE: Operation of unit on improper line voltage constitu tes
abuse and could affect unit reliability. See unit rating p late.D o n ot
installunit in system where voltagemay fluctuate above or below
permissible limits.
Make Electrical Connections
!WARNING
ELECTRICALSHOCK HAZARD
Failureto follow thiswarning could result inpersonal injury or
death.
Do not supply power to unit withcompressor terminal box
coverremoved.
NOTE: Use copper wire only betweendisconnect switchand unit.
NOTE: Install branch circuitdisconnect of adequatesize per NEC
tohandle unit starting current.Locate disconnectwithin sight from
and readily accessible from unit, per Section 440--14 of NEC.

Route Ground and Power Wires

Remove access panel to gain access to unit wiring. Extend wires
fromdisconnect through power wiringhole provided and into unit
controlbox.

Connect Groundand Power Wires

Connect ground wire to ground connection in control box for
safety.Connectpower wiring to contactoras shown in Fig. 7.
!WARNING
ELECTRICALSHOCK HAZARD
Failureto follow thiswarning could result in personalinjury or
death.
The unit cabinet must have an uninterrupted or unbroken
groundto minimize personal injuryif an electricalfault should
occur. The ground may consist of electrical wire or metal
conduit when installedin accordance with existing electrical
codes.
Connect ground wire to ground connection in control box for
safety.Connectpower wiring to contactoras shown in Fig. 7.
DISCONNECT
PER N.E.C. AND/OR
LOCAL CODES
CONTACTOR
GROUND
LUG
FIELD GROUND
WIRING
FIELD POWER
WIRING
BLUE
3 PHASE ONLY
A94025
Fig. 7 --Lin e Connections

Connect Control Wiring

Route 24v control wires through control wiring grommet and
connect leads to control wiring. See Thermostat Installation
Instructionsfor wiringspecific unit combinations.(See Fig. 8.)
UseNo. 18 AWG color--coded,insulated (35°C minimum) wire. If
thermostat is located more than 100 ft (30.5 m) from unit, as
measured along the control voltage wires, use No. 16 AWG
color--codedwire to avoid excessive voltagedrop.
All wiring must be NEC Class 1 and must be separated from
incoming power leads.
Use furnace transformer, fan coil transformer, o r accessory
transformerfor controlpower, 24v/40va minimum.
NOTE: Use of available 24v accessories may exceed the
minimum 40va power requirement.Determine total transformer
loading and increase the transformer capacity or splitthe load with
an accessory transformer as required.

FinalWiring Check

IMPORTANT:Check factory wiring and fieldwire connections
to ensure terminations are secured properly. Check wire routin g to
ensure wires are not in contact with tubing , sheet metal, etc.
CompressorCrankcaseHeater
When equipped with a crankcase heater, furnish power to heater a
minimum of 24 hr before starting un it.To furnish p ower to heater
only, set thermostat to OFF and clo seelectrical disconnect to
outdoorunit.
A crankcaseheater is required if refrigeranttubing is longer than
80 ft. (24.4m), or when outdoor unit is 20 ft. (6.1 m) belowthe
indoor unit. Refer to the Residential Piping and Long Line
Guideline.
25HCB3 / 25HCC5