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Fan Shaft Bearing Removal . . . . . . . . . . . . . . . . . . . 57
Fan and Shaft Removal . . . . . . . . . . . . . . . . . . . . . . . 59
Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Fan Sled Disassembly . . . . . . . . . . . . . . . . . . . . . . . . 59
SAFETY CONSIDERATIONS
Air-handling equipment is designed to provide safe and reliable
service when operated within design specifications. To avoid
injury to personnel and damage to equipment or property when
operating this equipment, use good judgment and follow safe
practices as outlined below.
DANGER
NEVER enter an enclosed fan cabinet or reach into a unit
while the fan is running.
LOCK OPEN AND TAG the fan motor power disconnect
switch before working on a fan. Take fuses with you and note
removal on tag. Electric shock can cause personal injury or
death.
LOCK OPEN AND TAG the electric heat coil power
disconnect switch before working on or near heaters.
WARNING
CHECK the assembly and component weights to be sure that
the rigging equipment can handle them safely. Note also, the
centers of gravity and any specific rigging instructions.
CHECK for adequate ventilation so that fumes will not
migrate through ductwork to occupied spaces when welding or
cutting inside air-handling unit cabinet or plenum.
WHEN STEAM CLEANING COILS be sure that the area is
clear of personnel.
DO NOT attempt to handle access covers and removable
panels on outdoor units when winds are strong or gusting until
you have sufficient help to control them. Make sure panels are
properly secured while repairs are being made to a unit.
DO NOT remove access panel fasteners until fan is completely
stopped. Pressure developed by a moving fan can cause
excessive force against the panel which can injure personnel.
DO NOT work on dampers until their operators are
disconnected.
BE SURE that fans are properly grounded before working on
them.
WARNING
DO NOT USE TORCH to remove any component. System
contains oil and refrigerant under pressure.
To remove a component, wear protective gloves and goggles
and proceed as follows:
a. Shut off electrical power to unit.
b. Recover refrigerant to relieve all pressure from system
using both high-pressure and low pressure ports.
c. Traces of vapor should be displaced with nitrogen and
the work area should be well ventilated. Refrigerant in
contact with an open flame produces toxic gases.
d. Cut component connection tubing with tubing cutter and
remove component from unit. Use a pan to catch any oil
that may come out of the lines and as a gage for how
much oil to add to the system.
e. Carefully unsweat remaining tubing stubs when neces-
sary. Oil can ignite when exposed to torch flame.
Failure to follow these procedures may result in personal
injury or death.
CAUTION
DO NOT re-use compressor oil or any oil that has been
exposed to the atmosphere. Dispose of oil per local codes and
regulations. DO NOT leave refrigerant system open to air any
longer than the actual time required to service the equipment.
Seal circuits being serviced and charge with dry nitrogen to
prevent oil contamination when timely repairs cannot be com-
pleted. Failure to follow these procedures may result in dam-
age to equipment.
CAUTION
SECURE drive sheaves with a rope or strap before working on
a fan to ensure that rotor cannot free-wheel.
DO NOT restore power to unit until all temporary walkways
inside components have been removed.
NEVER pressurize equipment in excess of specified test pres-
sures.
PROTECT adjacent flammable material when welding or
flame cutting. Use sheet metal or asbestos cloth to contain
sparks. Have a fire extinguisher at hand and ready for immedi-
ate use.
IMPORTANT: The installation of air-handling units and all
associated components, parts, and accessories which make
up the installation and subsequent maintenance shall be in
accordance with the regulations of ALL authorities having
jurisdiction and MUST conform to all applicable codes. It is
the responsibility of the installing contractor to determine
and comply with ALL applicable codes and regulations.
Field-supplied motors should be Underwriters Laboratories
(UL) or Canadian Standards Association (CSA) approved.
Field wiring must comply with National Electrical Code
(NEC) and all local requirements.