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Packaged Air-Conditioner Optional Parts
Base Heater
PAC-646BH-E
Before installation
• This product is designed for prevention of ice on the bottom of the outdoor unit heat exchanger and the clogged drain hole caused by
freezing in severe winter.
• To drain properly, a drain socket and a concentrated drain pan are not allowed to be used with this product.
SAFETY PRECAUTIONS
CAUTION
WARNING
• Carefully read this section ‘Safety Precautions’, and securely install the optional parts.
• Be sure to observe the cautions described here: They include critical contents for safety.
• The following indications show the classifications for danger, and possible consequences following incorrect handling.
Incorrect handling could lead to death or serious injury.
Incorrect handling could lead to injury or damage to house and household articles.
• After installation, perform a test run and make sure that there is no abnormality, and ask your customer to keep this installation sheet
with the installation manual at all times.
Also ask the customer to transfer these manuals to a new user if the user changes.
• If installed incorrectly by user, water leak, electric shock, fire, etc.
could result.
Ask the dealer or specialist for installation.
• Incorrect installation could cause water leak, electric shock, fire,
etc.
Carefully install the optional parts according to this instal-
lation sheet.
• Improper parts could cause electric shock, fire, water leak, and
injury caused by fall of the unit.
Use the provided parts and the specified parts for installation.
WARNING
• Improper connections and fastening could cause fire.
Use the specified electric wires. Connect and fasten the
electric wires securely to the terminals so external force on
the wires will not apply on the terminals.
• Incomplete installation may result in electric shock and fire
caused by dust, water, etc.
Mount the service panel on the outdoor unit securely.
• Failure to install an earth leakage breaker may result in electric
shock.
Install an earth leakage breaker.
• If the flammable gas should leak and accumulate around the unit,
explosion may result from it.
Do not install the unit where flammable gas may exist or leak.
CAUTION
• Do not connect the ground wire to a gas pipe, a water pipe, a
lightning rod, or a telephone ground wire. Improper grounding
may cause electric shock.
The grounding is performed with your hands touching the fins of
the heat exchanger. Wear protective equipment such as gloves
and the like in advance.
Ground the unit correctly.
1
Base heater
1
2
Heater support U
2
3
Heater support L
2
4
Heater plate
1
5
Cable tie
3
6
Fastener
2
7
Earth plate
1
8
Earth wire
2
9
Screw M4×8
8
0
Self-drilling screw
2
1
Spec label
1
2
Cable strap
2
It is easier to mount the base heater before installing the outdoor unit.
• Make sure that the main power supply to the unit is OFF.
• Do not lose the removed screws. Many screws will be removed to install the base heater.
• Eliminate dust, dirt, etc.
1) Remove the screw fixing the service panel.
2) Remove the service panel.
3) Remove the screws fixing the top panel.
4) Remove the top panel.
5) Remove the screws fixing the front panel.
6) Remove the front panel.
7) Remove the screws fixing the back panel.
8) Remove the back panel.
9) Disconnect the connectors (CN791, CN792, CN712, CNTH2,
CNTH1, CN797, CN63H, CNF1, and relay connector), and
remove the electrical box.
10) Removal of propeller fan.
Remove the mounting screws for the propeller fan. Pull the
propeller fan toward you to remove it.
11) Removal of motor support.
Disconnect the connector of the fan motor, and remove
mounting screw for the motor support. Slightly pull the motor
support toward you
and lift it up to remove it.
12) Remove the rear guard.
BH79J668H01
2 Preparation
3 Before installation
1 Accessories
(Fig 1)
Front panel
Propeller fan
Motor support
Top panel
Electrical box
Back
panel
Rear guard
Service panel
Before installation, follow the procedures below to remove some parts from the outdoor unit.
NOTE: Turn OFF power supply before disassembly.
This package includes the following parts besides this installation sheet.
BH79J668H01-5.indd 1
2017/04/13 15:22:43