McQuay ALP-067A Installation Manual

BULLETIN NO. IM

JULY 1978

173

INSTALLATION AND

MAINTENANCE DATA

PACKAGED AIR COOLED CONDENSING UNIT

TYPE ALP-067A THRU 159A

GROUP McQUAY-PERFEX Inc. 13600 Industrial Park Blvd., P.O. Box 1551, Minneapolis, Mn. 55440

NOTICE:

Installation and maintenance are to be performed only by

qualified personnel who are familiar with local codes and

regulations,

CAUTION:

injury hazard.

and experienced with this type of equipment.

Sharp edges and coil surfaces are a potential

Avoid contact.

page

Nomenclature

PROPELLER FANS LOW POWER CONSUMING AIR COOLED CONDENSER

Inspection

089 A D

REFRIGERANT CIRCUITS

(D=Dual;

S=Single)

DESIGN VINTAGE

NOMINAL CAPACITY (TONS)

When the equipment is received,

against the bill of lading to insure a complete shipment. should be carefully inspected for damage upon arrival.

all items should be carefully checked

All units

All shipping

damage should be 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.

INSTALLATION

Handling Care should be taken to avoid rough handling or shock due to dropping

the unit. base,

and block the pushing vehicle away from the unit to prevent

damage to the sheet metal cabinet.

FIGURE 1

Do not push or pull the unit from anything other than the

(See Figure 1.)

SUGGESTED PUSHING ARRANGEMENT

page

GOOD PUSHING ARRANGEMENT

CABINET DAMAGE UNLIKELY

POOR PUSHING ARRANGEMENT

CABINET DAMAGE LIKELY

Never allow any part of the unit to fall during unloading or moving as this may result in serious damage.

To lift the unit, of the unit.

2+"

diameter lifting holes are provided in the base

Spreader bars and cables should be arranged to prevent

damage to the condenser coils or unit cabinet.

FIGURE 2

SPREADER BAR

SUGGESTED LIFTING ARRANGEMENT

REQD.

-MUST USE THESE RIGGING HOLES

OTE

CONTROL 60x

(See Figure 2.)

L~cATI~NI

TABLE 1

ALP UNIT SIZE

067ASlD 078ASlD

089A 106A

UNIT WEIGHT

SHIPPING WEIGHTS

(Ibs)

4125

4308

4963 5134

ALP UNIT SIZE

126A 136A 149A 159A

UNIT WEIGHT

6021 6095 6873 7202

(Ibs)

Location Due to the vertical condenser design, it is recommended that certain

precautions be taken before installation to orient the unit so that prevailing winds blow parallel to the unit length thus minimizing effects on condensing pressure.

the unit in this manner,

a wind deflecting fence should be consi-

If it is not practical to orient

dered.

It is also necessary to provide adequate clearance on all sides of

the unit for service access and satisfactory performance.

60 in.

(1 fan diameter) should be allowed on each side of the unit

for condenser air inlet and compressor removal on units 067

At least

078. If parallel units are installed side by side, 120 in. should be allowed between units. atures and enhance system performance and operating economy.

This will prevent excessive condensing temper-

Clear-

ance for service access should be at least 78 in. at the control cen-

ter end for compressor removal on units 089 through 159 and 42 in.

on units 067 and 078.

the control center for ease of access to bearings and drives.

Allow 36 in.

clearance at the end opposite

These

clearances are illustrated in Figure 3.

page 5

FIGURE 3 CLEARANCE AROUND UNIT

CLEARANCE

(2)

NOTE:

60” MINIMUM CLEARANCE (2)

60”

MINIMUM

(I)

Minimum vertical clearance above unit should be 10

feet.

(2) Clearance to condenser coil must be increased if more

than one side is obstructed or between adjacent units. Consult your

McQUAY

sales representative.

Service Access Each end of the unit must be accessible after installation for peri-

odic service work.

Compressors and manual liquid line shutoff valves

are accessible from the control center end of the unit through re-

movable access panels on unit sizes 089 through 159 and hinged side

access doors on unit sizes 067 and 078. and starting controls are located in the unit control center. are protected by a keylocked,

internal"dead front"

doors for protection of service personnel from

weatherproof enclosure which contains

All operational, safety,

They

high voltage starting controls while servicing low voltage operational controls.

just below the main control center.

All resettable or adjustable controls are located

There is one resettable control

enclosure on each side of the unit and each enclosure contains con-

trols for compressors on that side of the unit.

Capped connections

for field service gauges are also located inside these enclosures. In addition,

each of these enclosures are removable to improve access

to compressors for field replacement.

The condenser fans, motors,

keylocked access door.

in,

and drives are accessible through a walkThe access door is located at the end of

the unit opposite the control center.

An internal fan guard is located below the condenser fans and drives on units 089 through 159.

This guard must be removed to service the

fan drives but MUST always be reinstalled when service work is com-

plete.

On unit sizes 067 and 078,

an interlock switch kills power to conden-

ser fans whenever the door is opened for service work on fans or

drives.

CAUTION:

Disconnect all power to the unit while servicing condenser fan drives.

page

Vibration Isolators Vibration isolators are recommended for all roof mounted installa-

tions or wherever vibration transmission is a consideration. 2 lists spring isolators for all ALP unit sizes.

Figure 4 shows

isolator locations in relation to the unit control center. gives dimensions that are required to secure each

McQuay

isolator

Table

Figure 5 selection to the mounting surface. Table 3 shows the isolator loads at each location shown in Figure 4

and the maximum loads for each McQuay selection.

TABLE 2

VIBRATION

ISOLATORS

216404B-27 2164046-26

TABLE 3

IS0 LATOR LOADS

page 7

REFRIGERANT PIPING

General

McQuay type ALP condensing units are adaptable to either chilled water or air handling air conditioning applications.

The only restriction on applications is that the evaporator be selected for a system using refrigerant 22.

Evaporator Above Condensing Unit

Figure 6 shows an installation where the evaporator is installed above the condensing unit.

It is shown for an air handling installation but all components shown are recommended for chilled water installations except that a refrigerant distributor is not usually required for shell-and-tube evaporators.

FIGURE 6

Legend Filter-drier

Solenoid valve Sight-glass/moisture indicator Thermal expansion valve

Suction line, pitched toward compressor

Liquid line Vibration absorber

EVAPORATOR ABOVE CONDENSING UNIT

Evaporator Below Condensing Unit

Notes:

1. Piping shown is for one circuit only, second circuit is similar.

2. All piping & piping components are by others.

Figure 7 shows an installation where the evaporator is installed below the condensing unit.

It is shown for an air handling installation but all components shown are recommended for chilled water installations except that a refrigerant distributor is not usually re-

quired for shell-and-tube evaporators.

Mote that a double suction

riser is shown for this arrangement. Risers

"A + B" are sized so that their combined cross-sectional in-

ternal area will allow full load unit operation without excessive

pressure drop (see notes, Table 4).

Riser

"B"

is sized to provide

adequate suction gas velocity for proper oil return at minimum load conditions.

in riser "A"

the trap shown in riser "A"

This riser becomes effective only when the trap shown

fills itself with oil.

It should be emphasized that

should be designed to contain a minimum internal volume to keep the total system oil requirements at a minimum.

Table 4 gives recommended line sizes for both single and double

suction lines and for liquid lines.

page

Figure 9 shows typical field wiring that is required for unit instal-

lation.

(SVl & SV2),

Items that require field wiring are:

optional hot gas bypass solenoid

liquid line solenoids

(SV5)

and the cooling

thermostat as well as the unit power supplies.

FIGURE 9

;BK

0 II

-FLOW SWITCH

PBl

DISCONNECT

BY OTHERS--\,,< TERMINAL BLOCK

3pH ---_H POWER SuppLy

_ _

SEPARATE POWER FOR CONTROLS

‘,‘--

DISCONNECT BY OTHERS

NOTE

FUSE-IO A

(C.W.

SYSTEMS)

___/-:__

II?,“-IOA

___

__I’_

TIME

CLOCK;;-

UNIT MAIN

REFRIGERANT CIRCUIT I SAFETY AND OPERATING

TYPICAL FIELD WIRING

OPTIONAL

TRANSFORMER

CONTROLS

FdSEU

CONI, llNlT

COMPRESSORS

AND FAN MOTORS

I i g_ ~~~SLT~OM~~~,~~NNECTION

LEGEND

irJH_WHlTt

SVl,2-LIOUID ’ INE

SVS-HOT

R3,4-COMP.

R5,6,7,E

PSI.2 -PUMPDOWN

TDl1,12,13-COMP

Rx-EVAP. FAN INTERLOCK

WlhlNG

SOL. VALVE

GAS BY PASS

SOL VALVE

384 START

RELAYS

-SAFETY

SWITCHES

CING TIME DELAYS

PREVENTS OPENING SV’S WITHOUT LOAD

RELAYS PROVIDE RECYCLING PUMP

DOWN DURING OFF

SEASON

fNEUT1.

RELAYS

SEOUEN-

PUMP STARTER CIRCUIT

CC. W.

SYSTEMS1

REFRIGERANT CIRCUIT SAFETY AND OPERATING

CONTROLS

UNIT CONDENSER

OPERATING CONTROLS

a0 __:

FANS

’

PUMP STARTER

RIO

-C

NOTE; CIRCUIT SHOWN ASSUMES CONTINUOUS

I I

POWER SUPPLY FOR CONTROLS

PUMP

OPERATIIN~FOR

PUMP OPERATION CONSULT

INTERMITTENT

McOUAY

Thermostat Wiring Since it is impossible for

McQuay to anticipate the type of installa-

tion that an ALP condensing unit may be used on, we do not factory

install a thermostat.

We do,

however,

provide numbered terminals in-

side the unit control center to which a thermostat may be connected. These terminals are shown and labeled "Terminals For Thermostat" on the electrical schematics.

On a two circuit unit it is important to connect the thermostat so that as successive stages of cooling are called for, the compressors

in the unit will be started to alternately increase the condenser load from refrigerant circuit 1 to circuit 2. in Table 9.

Figure 10 shows how to install 2 independent four stage

This is illustrated

thermostats for controlling an 8 stage unit and Figure 11 shows typical field wiring for an 8 stage thermostat.

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