York YLAA0195HE, Manual, Page: 131 / 206

131
JOHNSON CONTROLS
FORM 150.72-NM3 (1020)
ISSUE DATE 10/05/2020
6
COMMISSIONING
Commissioning of this unit should
only be carried out by Johnson Con -
trols Authorized personnel.
Commissioning personnel should be thoroughly familiar
with the information contained in this literature, in
addition to this section.
Perform the commissioning using the detailed checks
outlined in the “Equipment Pre-startup & Startup Check
List” (Page 133) as the commissioning procedure is
carried out.
PREPARATION – POWER OFF
The following basic checks should be made with the
customer power to the unit switched OFF.
Inspection
Inspect unit for installation damage. If found, take action
and/or repair as appropriate.
Refrigerant Charge
Packaged units are normally shipped as standard with a
full refrigerant operating charge. Check that refrigerant
pressure is present in both systems and that no leaks are
apparent. If no pressure is present, a leak test must be
undertaken, the leak(s) located and repaired. Remote
systems and units are supplied with a nitrogen holding
charge. These systems must be evacuated with a suitable
vacuum pump/recovery unit as appropriate to below
500 microns.
Do not liquid charge with static water in the cooler.
Care must also be taken to liquid charge slowly to avoid
excessive thermal stress at the charging point. Once the
vacuum is broken, charge into the condenser coils with
the full operating charge as given in the “Technical
Data ” section of ths IOM.
Service and Oil Line Valves
Open each compressor suction, economizer, and
discharge service valve. If valves are the back-seat type,
open them fully (counterclockwise) then close one turn
of the stem to ensure operating pressure is fed to pressure
transducers. Open the liquid line service valve and oil
return line ball valve fully in each system.
Compressor Oil
To add oil to a circuit – connect a YORK hand oil
pump (Part No. 470-10654-000) to the 1/4" oil charging
connection on the compressors with a length of clean
hose or copper line, but do not tighten the flare nut.
Using clean oil of the correct type (“V” oil), pump oil
until all air has been purged from the hose then tighten
the nut. Stroke the oil pump to add oil to the oil system.
Approximately 1.8-2.3 gallons is present in the each
refrigerant system.
Oil levels in the oil equalizing line sight glass should be
between the bottom and the middle of the sight glass with
the system off. High oil levels may cause excessive oil
carryover in the system. High oil concentration in the
system may cause nuisance trips resulting from incorrect
readings on the level sensor and temperature sensors.
Temperature sensor errors may result in poor liquid
control and resultant liquid overfeed and subsequent
damage to the compressor. While running, a visible sign
of oil splashing in the sight glass is normal.
Fans
Check that all fans are free to rotate and are not damaged.
Ensure blades are at the same height when rotated.
Ensure fan guards are securely fixed.
Isolation / Protection
Verify all sources of electrical supply to the unit are taken
from a single point of isolation. Check that the maximum
recommended fuse sizes given in the “Technical Data ”
section of ths IOM have not been exceeded.
Control Panel
Check the panel to see that it is free of foreign materials
(wire, metal chips, etc.) and clean out if required.
Power Connections
Check that the customer power cables are connected
correctly to the terminal blocks or optional circuit
breaker. Ensure that connections of power cables within
the panels to the circuit breaker or terminal blocks are
tight.
Grounding
Verify that the unit’s protective ground terminal(s) are
properly connected to a suitable grounding point. Ensure
that all unit internal ground connections are tight.
SECTION 6 – COMMISSIONING