Carrier 48KHA - Manual (Page 17)

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A WARNING
The ability to properly perform maintenance on this
equipment requires certain expertise, mechanical skills,
tools and equipment. If you do not possess these, do
not attempt to perform any maintenance on this equip­
ment other than those procedures recommended in the
Owner’s Manual. FAILURE TO HEED THIS WARN­
ING COULD RESULT IN SERIOUS PERSONAL
INJURY AND EQUIPMENT DAMAGE.
The minimum maintenance requirements for this equipment
are as follows:
1. Inspect air filter(s) each month. Clean or replace when
necessary.
2. Inspect cooling coil, drain pan, and condensate drain
each cooling season for cleanliness. Clean when
necessary.
3. Inspect blower motor and wheel for cleanliness and
check lubrication each heating and cooling season.
Service when necessary.
4. Check electrical connections for tightness and controls
for proper operation each heating and cooling season.
Service when necessary.
5. Check and inspect heating section before each heating
season. Clean and adjust when necessary.
A WARNING
Failure to follow these warnings could result in serious
personal injury.
1. Turn off gas supply, then disconnect electrical power
to unit before performing any maintenance or
service.
2. Use extreme caution when removing panels and
parts. As with any mechanical equipment, personal
injury can result from sharp edges, etc.
3. Never place anything combustible either on, or in
contact with unit.
4. Should overheating occur, or gas supply fail to shut
off, first shut off external main manual gas vedve to
unit, then shut off electrical supply.
Top Removal
A CAUTION
When removing unit top, use extreme caution to pro­
tect seal that isolates heat exchanger and flue products
from other sections. Removal of top must never be
attempted by anyone other than qualified technicians.
A CAUTION
Condenser fan and motor are fastened to unit top.
When removing top, use extreme ceire not to pull fan
motor leads loose.
NOTE: When performing maintenance or service proce­
dures that require removal of unit top, be sure to perform all
routine maintenance procedures that require top removal,
including: inspection of heat exchanger area, coil inspection
and cleaning, and condensate drain pan inspection and
cleaning.
When performing mEuntenemce and service procedures that
require unit top removal, refer to following top removal
procedures:
1. Turn off gas supply, then disconnect electric power to
unit.
2. Remove vent cap and combustion-air assemblies. Do
not damage gasket. Refer to Venting section and
reverse assembly procedures shown.
3. Remove all screws that secure unit top, including
screws around 4 sides and those on top that screw into
internal divider panels. Save all screws.
4. Tape all side panels at each seam near unit top. Use
tape strips that are at least 5 in. long to prevent sides
from falling when top is removed.
5. Carefully lift top from unit. Set top on edge and ensure
that it is supported by unit side that is opposite duct
(or plenum) side. Use extreme care to prevent damage
to either seal that isolates heat exchanger and flue
products, or the fan blades, motor and insulation.
A WARNING
If seal that isolates heat exchanger and flue products is
damaged, repair seed, using same type of foil-backed
insulation used at time of manufacture, and/or alumi­
num duct tape, depending on severity of damage.
FAILURE TO HEED THIS WARNING COULD
RESULT IN SERIOUS PERSONAL INJURY TO
OCCUPANTS OF THE CONDITIONED SPACE.
6
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7.
Carefully replace and secure unit top to unit, using
screws removed in step 3 when maintenance and/or
service procedures are concluded. Be sure to use origi­
nal screws that have rubber washers to seal out water
when securing top to internal divider panels.
Reinstall vent cap and combustion-air assemblies.
Refer to Venting section.
Air Filter
A CAUTION
Never operate unit without a suitable air filter in
return-air duct system. Always replace filter with same
size and type. See Table 2 for filter sizes.
Inspect field-supplied Eur filter(s) at least once each month
and replace (disposable type) or clean (cleanable type) at
least twice during each heating and cooling season or when­
ever the filter(s) becomes clogged with dust and lint.
Evaporator Blower Wheel and Motor— For longer life, oper­
ating economy and continuing efficiency, clean accumulated
dirt and grease from blower wheel and motor annually.
Lubricate motor every 5 years if motor is used intermit­
tently (thermostat FAN switch in AUTO, position), or every
2 years if motor is used continuously (thermostat FAN
switch in ON position).
A WARNING
Turn off gas supply, then disconnect and tag electricEd
power to unit before cleaning and lubricating blower
motor and wheel. Failure to do so may cause personal
injury or death.
Clean and lubricate blower motor and wheel as follows:
1. Remove Emd disassemble blower assembly.
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