General; Electrostatic Discharge (Esd) Precautions - Carrier 58MXA Service And Maintenance Instructions

Fig. 1—Multipoise Furnace in Upflow Orientation
Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained and qualified
service agency personnel should install, repair, or service
heating equipment. Untrained personnel can perform basic
maintenance functions described in User's Information
Manual such as cleaning and replacing air filters. All other
operations must be performed by trained and qualified service
agency personnel. When working on heating equipment, observe
precautions in the literature, on tags, and on labels attached to or
shipped with the unit and other safety precautions that may apply.
Follow all safety codes including the National Fuel Gas Code
(NFGC) NFPA 54-2002/ANSI Z223.1-2002 in the U.S.A.; Na-
tional Standard of Canada, Natural Gas and Propane Installation
Code CSA B149.1-00 (NSCNGPIC) in Canada; and the Installa-
tion Standards, Warm Air Heating and Air Conditioning Systems
(NFPA 90B) ANSI/NFPA 90B. Wear safety glasses and work
gloves. Have a fire extinguisher available during start-up and
adjustment procedures and service calls.
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ELECTRICAL SHOCK AND UNIT DAMAGE
HAZARD
Failure to follow this caution may result in minor personal
injury or damage to furnace.
Label all wires prior to disconnection when servicing con-
trols. Wiring errors can cause improper and dangerous
operation.
These instructions are written as if the furnace is installed in an
upflow application. An upflow furnace application is where the
blower is located below the combustion and controls section of the
furnace, and conditioned air is discharged upward. Since this
furnace can be installed in any of the 4 positions shown in Fig. 2,
you may need to revise your orientation to component location
accordingly.

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS

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UNIT DAMAGE HAZARD
Failure to follow this caution may damage furnace compo-
nents.
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Electrostatic discharge can affect electronic components.
Take precautions during furnace installation and servicing to
protect the furnace electronic control. Precautions will pre-
vent electrostatic discharges from personnel and hand tools
which are held during the procedure. These precautions will
help to avoid exposing the control to electrostatic discharge
by putting the furnace, the control, and the person at the same
electrostatic potential.
1. Disconnect all power to the furnace. DO NOT TOUCH THE
CONTROL OR ANY WIRE CONNECTED TO THE CON-
TROL PRIOR TO DISCHARGING YOUR BODY'S ELEC-
TROSTATIC CHARGE TO GROUND.
2. Firmly touch a clean, unpainted, metal surface of the furnace
chassis which is close to the control. Tools held in a person's
hand during grounding will be satisfactorily discharged.
3. After touching the chassis, you may proceed to service the
control or connecting wires as long as you do nothing that
recharges your body with static electricity (for example; DO
NOT move or shuffle your feet, DO NOT touch ungrounded
objects, etc.).
HORIZONTAL
AIRFLOW
2

GENERAL

AIRFLOW
UPFLOW
LEFT
DOWNFLOW
AIRFLOW
Fig. 2—Multipoise Orientation
HORIZONTAL
RIGHT
AIRFLOW
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