10
Pre-Startup Instructions
On new installations, or if a major component has been
replaced, the operation of the unit must be checked.
Check unit operation as outlined in the following
instructions. If any sparking, odors, or unusual sounds
are encountered, shut off electrical power and recheck for
wiring errors, or obstructions in or near the blower motors.
Duct covers must be removed before operating unit.
The Startup, Adjustments, and Checks procedure provides
a step-by-step sequence which, if followed, will assure the
proper startup of the equipment in the minimum amount of
time. Air balancing of duct system is not considered part
of this procedure. However, it is an important phase of any
air conditioning system startup and should be performed
upon completion of the Startup, Adjustments, and Checks
procedure. The Startup, Adjustments, and Checks
procedure at outside ambients below 55°F should be
limited to a readiness check of the refrigeration system with
the required final check and calibration left to be completed
when the outside ambient rises above 55°F.
Temporary Heating Or Cooling
If the unit is to be used for temporary heating or cooling, a
“Startup, Adjustments, and Checks” must first be performed
in accordance with this manual. Damage or repairs due to
failure to comply with these requirements are not covered
under the warranty.
After
the machines are used for
temporary heating or cooling, inspect the coils, fans, and
motors for unacceptable levels of construction dust and dirt
and install new filters.
Contractor Responsibility
The installing contractor must be certain that:
•
All supply and return air ductwork is in place,
properly sealed, and corresponds with installation
instructions.
•
All thermostats and sensors are mounted and wired
in accordance with installation instructions.
•
All electric power, all gas, hot water or steam line
connections, and the condensate drain installation
have been made to each unit on the job. These
main supply lines must be functional and capable of
operating all units simultaneously.
•
All filters are in place.
Roof Curb Installation Check
Inspect the roof curb for correct installation. The unit and
curb assembly should be level. Inspect the flashing of the
roof mounting curb to the roof, especially at the corners, for
good workmanship. Also check for leaks around gaskets.
Note any deficiencies in a separate report and forward to
the contractor.
Obstructions, Fan Clearance and Wiring
Remove any extraneous construction and shipping
materials that may be found during this procedure. Rotate
all fans manually to check for proper clearances and that
they rotate freely. Check for bolts and screws that may
have jarred loose during shipment to the job site.
Re-tighten if necessary. Re-tighten all electrical
connections.
Field Duct Connections
Verify that all duct connections are tight and that there is no
air bypass between supply and return.
Filter Section Check
Remove filter section access panels and check that filters
are properly installed. Note airflow arrows on filter frames.
Pre-startup Precautions
It is important to your safety that the unit has been properly
grounded during installation. Check ground lug connection
in main control box for tightness prior to closing circuit
breaker or disconnect switch. Verify that supply voltage
on line side of disconnect agrees with voltage on unit
identification plate and is within the utilization voltage range
as indicated in Appendix B Electrical Data.
System Voltage -
That nominal voltage value assigned
to a circuit or system for the purpose of designating its
voltage class.
Nameplate Voltage -
That voltage assigned to a piece of
equipment for the purpose of designating its voltage class
and for the purpose of defining the minimum and maximum
voltage at which the equipment will operate.
Utilization Voltage -
The voltage of the line terminals
of the equipment at which the equipment must give fully
satisfactory performance. Once it is established that supply
voltage will be maintained within the utilization range under
all system conditions, check and calculate if an unbalanced
condition exists between phases. Calculate percent voltage
unbalance as follows:
Three Phase Models Only
AIR FLOW ADJUSTMENTS
When the final adjustments are complete, the current
draw of the motor should be checked and compared to
the full load current rating of the motor. The amperage
must not exceed the service factor stamped on the motor
nameplate.
