McQuay ALR-012A Installation Manual
BULLETIN NO. IM 207
MAY, 1980
INSTALLATION AND
MAINTENANCE DATA
o-
GROUP
PACKAGED AIR COOLED WATER CHILLER
TYPE ALR-012A THRU 030A
McQuay-PERFEX Inc.
13500 Industrial Park Blvd., P.O. Box 1551, Minneapolis, Mn. 55440
@
INTRODUCTION
McQUAY
automatic water cooling units that include the latest in
engineered components arranged to provide a compact and
efficient unit. Each unit is assembled before evacuation,
charging and testing. Each unit consists of an air cooled
condenser with integral subcooler section, unloading
compressor and replaceable tube, shell-and-tube evaporator.
ALR SEASONPAK air cooled water chillers are
NOMENCLATURE
A L R-030 A-S
Air Cooled Condensing
Reciprocating Compressor
INSPECTION
When the equipment is received, all items should be
carefully checked against the bill of lading to insure a
complete shipment. All units should be carefully inspected
for damage upon arrival. All shipping damage should be
INSTALLATION
NOTE: Installation and maintenance are to be performed only by qualified personnel who are familiar
with local codes and regulations, and experienced with this type of equipment. CAUTION: Sharp edges
and coil surfaces are a potential injury hazard. Avoid contact with them.
HANDLING
Care should be taken to avoid rough handling or shock due
to dropping the unit. Do not push or pull the unit from
anything other than the base, and block the pushing vehicle
away from the unit to prevent damage to the sheet metal
cabinet (See Figure 1). Do not let the lifting fork damage
the refrigerant piping within the cabinet.
To lift the unit, 2
provided in the base of the unit. Spreader bars and cables
should be arranged to prevent damage to the condenser
coils or unit cabinet (See Figure 2).
-1/2-inch
diameter lifting holes are
Liquid line components included are manual liquid line
shutoff valve, replaceable core filter-drier, liquid line
solenoid valve, sightglass/moisture indicator and double
diaphragm hydraulic element thermal expansion valve.
Other features include: compressor crankcase heater, an
evaporator heater for chilled water freeze protection and
recycling pumpdown during “on” or “off” seasons.
Nominal Capacity (Tons)
reported to the carrier and a claim should be filed. The unit
serial plate should be checked before unloading the unit to
be sure that it agrees with the power supply available.
FIGURE 1. SUGGESTED PUSHING ARRANGEMENT
r
BLOCKING
LOCATION
Due to vertical condenser design, it is recommended that
the unit be oriented so that prevailing winds blow parallel
to the unit length, thus minimizing effects on condensing
pressure.
manner, a wind deflector should be constructed.
mounted on a roof or concrete slab (ground level
installation). Roof-mounted units should be installed level
on steel channels or an l-beam frame to support the unit
above the roof. Use of vibration pads or isolators is
recommended. The roof must be strong enough to support
the weight of the unit. See Table 1 for unit weights.
Concrete slabs used for unit mounting should be installed
level and be properly supported to prevent settling. A
one-piece concrete slab with footings extended below the
frost line is recommended.
TABLE 1.
If it is not practical to orient the unit in this
Units are designed for outdoor application and may be
UNIT WEIGHTS
ALR MODEL
012
015
020
025
030
OPERATING WEIGHT
1364
1661
1883
2012
2330
(LBS.)
GOOD PUSHING ARRANGEMENT -CABINET DAMAGE UNLIKELY
FIGURE 2.
PAGE 3
WATER PIPING
PIPING PRACTICES
5.
Due to the variety of piping practices; it is advisable to
follow the recommendations of local authorities. They can
supply the installer with the proper building and safety
codes required for a safe and proper installation.
Basically, the piping should be designed with a
minimum number of bends and changes in elevation to
keep system cost down and performance up. It should
contain:
Vibration eliminators to reduce vibration and noise
transmission to the building.
Shut-off valves to isolate the unit from the piping
system during unit servicing. prevent moisture condensation and possible damage to the
Manual or automatic air vent valves at the high points
of the system.
Some means of maintaining adequate system water
pressure (e.g., expansion tank or regulating valve).
COOLER WATER CONNECTIONS
Temperature and pressure indicators located at the unit
to aid in unit servicing.
6.
A strainer or some means of removing foreign matter
from the water before it enters the pump. It should be
placed far enough upstream to prevent cavitation at the
pump inlet (consult pump manufacturer for
recommendations). The use of a strainer will prolong
pump life and thus keep system performance up.
Prior to insulating the piping and filling the system, a
preliminary leak check should be made.
Piping. insulation should include a vapor barrier to
building structure. It is important to have the vapor barrier
on the outside of the insulation to prevent condensation
within the insulation on the cold surface of the pipe.
It is suggested that horizontal water piping connections to
the cooler be made through the holes provided in the base
frame. Two suggested arrangements that will align the
7. Vertical connections may be made to the cooler through
the open base using
2-inch
IPS
90-degree
elbows. Figure 10
gives the necessary dimensions for either piping method.
piping with the base frame holes are shown in Figures 6 and
FIGURE 6.
FIELD
P-
2” IPS WATER PIPE
NOTE: FOR INSTALLING A CHILLED WATER THERMOSTAT IN
RETURN WATER LINE A REDUCING TEE
SE USED INSTEAD OF A 2” IPS 90 ELBOW. SEE FIGURE 8.
-
COOLER WATER CONNECTIONS
INSTA
2”
IPS STREET ELBOW
BASE FRAME
”
IPS WATER CONNECTION
(2” x
1/2” x
2”)
MAY
CHILLED WATER THERMOSTAT
The chilled water thermostat is mounted inside the unit
FIGURE 7.
FIELD INSTALLED
I
L
FIGURE 8.
OOLER WITH 2” IPS CONNECTION
”
IPS
45’
ELBOW
BASE FRAME
2” IPS WATER PIPE
THERMOSTAT SENSOR INSTALLATION
control center. The sensor must be installed in the return
water line as shown in Figure 8. The thermostat sensor
should be insulated after installation.
REDUCING TEE
THERMOSTAT
12”~ l/Z” x 2”)
BULB
W
FIELD INSTALLED
CAUTION: Thermostats have maximum operating
temperature limits of
125OF on return water. Temperatures
exceeding these limits may damage the controls.
ETURN
WATER
THERMOSTAT SENSO EVAPORATOR
RETURN WATER
LINE
CONNECTION OF
PAGE 5
FLOW SWITCH
A water flow switch or pump starter interlock is required to
insure that there will be adequate water flow and cooling
load to the evaporator before the unit can start. This will
safeguard against slugging the compressors on start-up. It
also serves to shut down the unit in the event that water
flow is interrupted to guard against evaporator freeze-up.
A flow switch is available from
ordering number 860-175033X-00. It is a “paddle” type
switch and adaptable to any pipe size from l-inch to 6-inch
nominal. Certain minimum flow rates are required to close
McQUAY
under
the switch and are listed in Table 4. Installation should be
as shown in Figure 9.
Electrical connections in the unit control center should
be made at terminals 12 and 21. The normally open
contacts of the flow switch should be wired between these
two terminals. There is also a set of normally closed
contacts on the switch that could be used for an indicator
light or an alarm to indicate when a “no flow” condition
exists.
TABLE 4. FLOW SWITCH MINIMUM FLOW RATES
NOMINAL
PIPE SIZE
(INCHES)
1
l/4
1
1/2
2
MINIMUM REQUIRED
FLOW TO ACTIVATE
SWITCH (GPM)
9.80
12.70
18.80
FIGURE 10. DIMENSIONAL DRAWING
68.60 OPENING (AIR
WATER CONN.
CLEARANCE HOLES
3.62 DIA.
(2)
OUTLET SCREEN
NOT SHOWN)
-
FIGURE 9.
FLOW SWITCH
NO RESTRICTIONS
5
PIPE DIAMETERS MIN.
AFTER SWITCH
FLOW DIRECTION
MARKED ON SWITCH
NO RESTRICTIONS
5 PlPE DIAMETERS MlN
BEFORE SWITCH
(FIELD MOUNTED)
OPTIONAL
PAGE 6
#
14.761
LIFTING HOLES
2.50 DIA.
(2
EACH SIDE)
MOUNTING HOLES,
.750 DIA. (2 EACH
SIDE)
ALR
UNIT SIZE
012A-S
015A-S
020A-S
025AS
030A-S
POWER CONN.
J
/
k
46.00
MOUNTING HOLES
DIMENSIONS & CONNECTIONS
A
50.60
50.60
65.60
65.60
80.60
DIMENSIONS (INCHES)
B
48.88,
Inlet
36.88,
Inlet
36.88, Inlet
36.88, Inlet
Outlet
14.02,
C
7.20,Outlet
7.20.
Outlet
7.20,
Outlet
7.20,Outlet
18.06, Inlet
WATER CONN. SIZE
2”I.P.S.
2”I.P.S.
I
.P.S.
2”
2”I.P.S.
2”
I
.P.S.
REFRIGERANT
ADDING REFRIGERANT CHARGE
On systems that have been previously charged with
refrigerant, an insufficient charge is indicated by bubbling
in the sightglass. On uncharged systems the system should
be leak tested and evacuated before charging.
Upon charging a system the discharge and suction
shut-off valves on the compressor should be open and there
should be normal water flow through the cooler.
CAUTION: Do not make any safety controls
inoperative during the charging operation; cooler damage
from freezing may result.
Back seat the liquid line shut-off valve and connect the
1.
charging hose to the
2.
Install pressure gauges and review start-up instructions.
3.
Purge the charging hose and open the charging cylinder
to allow refrigerant into the system.
When removing the refrigerant on water chiller systems to
prevent freeze-up, either drain the water or circulate the
water. If water cannot be drained, make sure the cooler
heater is energized; do not remove refrigerant rapidly since
this can cause freeze-ups. Have a sufficient number of
refrigerant containers at hand and a scale for weighing
them. The containers should be clean, dry and empty.
To transfer the refrigerant to a container connect the
gauge manifold from the compressor discharge valve service
port to the container and purge the lines. Note the capacity
l/4-inch
flare connection.
REMOVING REFRIGERANT CHARGE
4.
Turn the liquid line shut-off valve in three turns to
permit a back flow of refrigerant into the subcooler.
After refrigerant stops flowing into the system, close
5.
the liquid line shut-off valve. Start the compressor to
charge the system.
6.
If the amount of refrigerant has been predetermined,
add this amount and check the sightglass afterward. If
the amount of charge is unknown, every five minutes
close the charging cylinder valve, open the liquid line
shut-off valve and check for proper charge by
examining the sightglass. Continue charging and
checking the sightglass until it
NOTE: Fluorocarbon refrigerants should not be
released to the atmosphere. For a means
to the following section.
of the container. Place the container in ice to cool the
container so the fusible plug does not melt as the condenser
condenses. Operate the compressor normally. Turn the
discharge service valve in three turns to open the service
port. Open the container valve and the gauge manifold. Do
not close off the discharge valve to the condenser; discharge
gas can enter the container and condense. Frequently weigh
the container so as not to overfill. When the container is
filled use additional ones.
clears.
I
of
recovery, refer
FIELD WIRING
Wiring should be done in accordance with all applicable
codes and ordinances. Warranty is voided if wiring is not in
accordance with specifications. An open fuse indicates a
short, ground or overload. Before replacing a fuse or
restarting a compressor or fan motor, the trouble must be
found and corrected.
Copper wire is required for all power lead terminations
at the unit.
All unit sizes are set up as standard for separate 115
volt power supply circuits for the control circuit and cooler
heater. The control circuit only, or both the control circuit
-
and the cooler heater, can be powered off the main unit
power supply if the optional control circuit transformer is
ordered. It may be desirable, however, to have the unit
cooler heater on a separate disconnect switch from the
main unit power supply so that the unit may be shut down
without defeating the freeze protection provided by the
cooler heater.
A standard feature on all ALR units is COPS
(Controlled Override of Pump Shut-down), a system for
interlocking
chiller control system. Relay RI9 is wired into the unit
control circuit so that a time clock and/or ambient
thermostat can be connected to a pair of terminals (14 and
15) inside the unit control center. The time clock can
energize a pump starter. Once the pump starts, the flow
switch and/or pump interlock will close and energize that
part of the control circuit that will allow the unit to start.
This feature makes it possible to start the chilled water
pump and the chiller simultaneously only when cooling is
required. For recycling
cooling, a relay (energized by the low pressure control) is
also wired into this circuit to start the pump, close the flow
switch and pump down the unit.
NOTE: If a time clock, ambient thermostat and/or
remote on-off switch are not used, terminals 14 and 15
must be
Figure 11 shows typical field wiring that is required for
unit installation.
the field supplied chilled water pump into the
pumpdown without a demand for
jumpered together before the unit will start.
PAGE 7
TABLE 6.
COMPRESSOR & CONDENSER FAN MOTORS
ALR
UNIT SUPPLY
SIZE
012A
015A
020A
025A
030A
NOTES:
ELEC.
(1)
208
230
380
460
208
230
380
460
208
230
380
460
208
230
380
460
208
230
380
460
1. Voltage limits:
RATED LOAD AMPS (2)
COMP. FAN MOTORS
44.0 4.4
44.0 4.4
22.0 2.4
22.0 2.4
64.0 4.4
64.0 4.4
32.0 2.4
32.0 2.4
80.0 4.4
80.0
41.0 2.4
41 .o
98.0 4.4
98.0 4.4
53.0 2.4
53.0 2.4
121.0 4.4
121 .o
61 .O
61 .O
Nameplate 208-Max.
Nameplate 230-Max.
Nameplate 380-Max.
Nameplate 460-Max.
FAN MOTOR
(EACH)
4.4
2.4
4.4
2.4
2.4
229V,
253V, Min.
418V,
506V.
NO.
OF
MOTORS (EACH)
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Min. 187V.
207V.
Min. 342V. first winding.
Min. 414V.
FAN
8.2
8.2
7.5
7.5
8.2
8.2
7.5
7.5
8.2
8.2
7.5
7.5
8.2
8.2
7.5
7.5
8.2
8.2
7.5
7.5
2. Compressor rated load amps are for wire sizing purposes only
3. Compressor locked rotor amps for part-winding start is for the
ACROSS-THE-LINE-START
do not reflect normal operating current draw.
LOCKED ROTOR AMPS
PART-WINDING-START
COMPRESSOR
228 _
228
114
114
308 188
308 188
154 _
154 _
428 250
428 250
214 _
214
470 292
470 292
235
235 _
565 340
565 340
283 _
283
COMPRESSOR
_
_
-
and
START-UP & SHUT-DOWN
PRE START-UP
With all electric disconnects open, check all screw or lug
1.
type electrical connections to be sure they are tight for
good electrical contact. Check all compressor valve con-
nections for tightness to avoid refrigerant loss at startup. Although all factory connections are tight before
shipment, some loosening may have resulted from ship-
ping vibration.
2.
Inspect all water piping for flow direction and correct
connections at the evaporator.
3.
Open all water flow valves and start the chilled water
pump. Check all piping for leaks and vent the air from
the evaporator as well as from the system piping. Flush
the evaporator and system piping to obtain clean,
non-corrosive water in the evaporator circuit.
4.
Check to see that the thermostat water temperature
sensor is installed in the return water line (return to
chiller). The sensor well should be full of heat
conducting compound and the sensor should be secured
in the well with the retaining clip provided.
5.
Check the compressor oil level. Prior to start-up, the oil
level should cover at least
6.
Check the voltage of the unit power supply and see that
it is within the
*IO%
voltage unbalance must be within 42%.
7.
Check the unit power supply wiring for adequate
ampacity and a minimum insulation temperature rating
of 75c.
8.
Verify that all mechanical and electrical inspections
have been completed per local codes.
1/2
of the oil sightglass.
tolerance that is allowed. Phase
9.
See that all auxiliary control equipment is operative and
that an adequate cooling load is available for initial
start-up.
10. Making sure control stop switch
pumpdown
pumpdown,”
switches PSI and PS2 are on “manual
throw the main power and control discon-
S1
is open (off) and
nect switches to “on.” This will energize the crankcase
heaters. Wait a minimum of 12 hours before starting
unit.
CAUTION: Most relays and terminals in the unit control center are hot with
connect on.
S1 and the control circuit dis-
START-UP
Double check that the compressor suction and dis-
1.
charge shut-off valves are back seated. Always replace
valve seal caps.
Open the manual liquid line shut-off valve at the outlet
2.
of the subcooler.
Allow the crankcase heater to operate for at least eight
3.
hout
s
prior to start-up.
Check to see that the
4.
“manual pumpdown”
switch
5.
Adjust the dial on temperature controller
(S1)
is in the “on” position.
pumpdown
position and the control stop
desired chilled water temperature.
Start the auxiliary equipment for the installation by
6.
turning
on the time clock, ambient thermostat and/or
switch PSI is in the
TC1
to the
PAGE 9
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