York YCAS0295EB, Installation Operation & Maintenance

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40 YORK INTERNATIONAL
FORM 201.19-NM7 (804)
or cop per line, but do not tighten the fl are nut. Using
clean oil of the correct type (“L” oil), pump oil until all
air has been purged from the hose then tight en the nut.
Stroke the oil pump to add oil to the oil sys tem. The oil
level should be between the mid dle of the low er and
mid dle of the up per sight glasses of the oil sep a ra tor.
Ap prox i mate ly 5 gal lons is present in the entire chill er
system, with 1-2 gal lons in the oil separator.
Fans
Check that all fans are free to rotate and are not dam-
aged. Ensure blades are at the same height when ro tat ed.
Ensure fan guard is securely fi xed.
Isolation/Protection
Verify that all sources of elec tri cal supply to the unit
are taken from a single point of iso la tion. Check that
the maximum recommended fuse siz es given in the
Tech ni cal Data Section have not been exceeded.
Control Panel
Check the panel to see that it is free of foreign ma te ri als
(wire, metal chips, etc.) and clean out if required.
Power Connections
Check to assure the customer power ca bles are connected
cor rect ly. Ensure that con nec tions of power cables within
the panels to the circuit breakers, terminal blocks or
switch disconnectors are tight.
Grounding
Verify that the unit’s protective terminal(s) are prop er ly
connected to a suitable grounding point. Ensure that all
unit internal ground connections are tight.
Overloads
Ensure that the fan overloads settings are correct for the
type of fan fi tted.
Supply Voltage
Verify that the site voltage supply cor re sponds to the
unit requirement and is within the lim its given in the
Tech ni cal Data Section.
Control Transformer
The 3-wire control transformer is mounted external to
the panel. It is important to check that the correct pri ma ry
tapping has been used:
With the supply voltage to the unit turned off, remove
the lid to the transformer box.
COMMISSIONING
PREPARATION
Commissioning of this unit should
only be car ried out by YORK Au tho -
rized per son nel.
The Millennium Microcomputer Con trol Sys tem
Op er at ing In struc tions must be read in con junc tion
with this sec tion.
PREPARATION – POWER OFF
The following checks should be made with the cus tom er
supply/supplies to the unit switched OFF.
Inspection
Inspect unit for installation dam age. If damage is found
take ac tion and/or repair as appropriate.
Refrigerant Charge
Units are normally shipped as stan dard with a full
re frig er ant operating charge. Check that refrigerant
pres sure is present in both systems and that no leaks
are ap par ent. If no pressure is present a leak test must be
un der tak en. The leak(s) should be located and re paired.
Re paired sys tems and units supplied with a ni tro gen
hold ing charge must be evacuated with a suit able vac-
uum pump/re cov ery unit as appropriate to be low 100
microns.
Do not liquid charge with static water in the evaporator.
Care must also be taken to liquid charge slowly to avoid
ex ces sive 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.
Valves
Open each compressor suction, economizer, and dis-
charge valve ful ly (counter-clockwise) then close one
turn of the stem to ensure operating pressure is fed to
the pres sure trans duc ers. Open the liquid line service
valve ful ly and en sure the oil re turn line ball valve is
open 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 valve
on the oil separator piping with a length of clean hose
Commissioning