JOHNSON CONTROLS
87
SECTION 3 – START-UP
FORM 145.05-NOM7
ISSUE DATE: 10/31/2019
CRANKCASE HEATERS
The purpose of the crankcase heater is to prevent the
migration of refrigerant to the crankcase during shut-
down, assuring proper lubrication of the compressor
on start-up.
The heater is interlocked with the compressor contactor
and is not controlled directly by the microprocessor.
When the compressor is OFF, a normally closed aux-
iliary contact on the compressor contactor closes the
circuit and applies power to the crankcase heater.
Anytime power is removed from the unit for more than
an hour, the crankcase heater should be left ON for 24
hours prior to start.
PRE-STARTUP REQUIREMENTS
1. Inspect the unit for shipping or installation dam-
age.
2. Verify the unit is completely and properly installed
with ductwork connected. Verify that all construc-
tion debris is removed and filters are clean.
3. With all electrical disconnects open, check all
electrical connections to be sure they are tight.
4. Visually check for refrigerant piping leaks.
To protect warranty, this equipment must
be installed and serviced by an authorized
Johnson Controls service mechanic or a
qualified service person experienced in
air handling and condenser unit instal-
lation. Installation must comply with all
applicable codes, particularly in regard to
electrical wiring and other safety elements
such as relief valves, HP cut-out settings,
design working pressures and ventilation
requirements consistent with the amount
and type of refrigerant charge.
Lethal voltages exist within the control
panel. Before servicing, open and tag all
disconnect switches.
Power must be applied to the unit 24 hours
prior to starting the unit compressors.
Failure to observe this requirement can
lead to compressor damage and voiding
of the compressor warranty.
SECTION 3 – START-UP
5. Verify the unit condenser water connections and
condensate drain connections have been piped.
6.
Check for proper water flow according to
mining Water Flow (Condenser Only) on page
and
Determining Water Flow (Waterside
Economizer Active) on page 98.
7. The compressor oil level should be maintained so
that an oil level is visible in the sight glass. The
oil level can only be tested when the compressor
is running in stabilized conditions, guaranteeing
there is no liquid refrigerant in the lower shell of
the compressor. With the compressor running,
the oil should be between 1/4 and 3/4 in the sight
glass. At shutdown, the oil level can fall to the
bottom limit of the oil sight glass.
Not all compressors come with an oil
sight glass. Most compressors use an oil
level port located a few inches up from
the bottom.
8. Check the control panel to assure it is free of for-
eign material (wires, metal chips, etc).
9.
Visually inspect field wiring (power and control).
Wiring must meet NEC and local codes.
10. Verify fuse sizing in main circuits.
11. On VAV and FlexSys units verify the pneumatic
tubing has been field installed between the pres
-
sure transducer in the unit and the probe(s) in the
ductwork or underfloor space.
12. Check the tightness of setscrews in bearings,
drives, and fan wheels
13. Verify the supply fan shipping restraint bolts have
been removed
(refer to Figure 24 on page 39).
14. Verify the supply fan rotates freely. Verify proper
drive alignment of the supply fan.
92 and 81 for proper procedure.
15. Verify the entering and leaving condenser water
temperature sensors are mounted.
16. Verify the return air temperature sensor and op-
tional outdoor temperature sensors have been in-
stalled and that the wiring has been made to the
Unit Controller Board.
Refer to Unit Wiring Dia-
gram.
(See 145.05-SU7)