McQuay PWA008 Installation Manual

BULLETIN NO. IM 105

MAY 1966

INSTALLATION AND

MAINTENANCE DATA

PWA

PACKAGED WATER CHILLER

7% THRU 60 TONS

INC. l 13600 INDUSTRIAL PARK BLVD., P.O. BOX 1551, MINNEAPOLIS, MINNESOTA 55440

PHONE:

377-9750

AREA CODE: 612

PRE-INSTALLATION

LOCATION

A.

Unit

is designed for indoor application and must
be located in an area where the surrounding am­bient temperatures are 40 F or above. A good rule
of thumb is to place units where ambients are at

least 5 degrees above the leaving water tempera-

t

urc

B.

Because of the electric control devices, the units

should not be exposed to the weather. A plastic
cover over the control box is supplied as temporary
protection during transfer.

A reasonably level and sufficiently strong floor

c.

is all that is required for the Seasonpak Water

Chiller. If necessary,
bers should be provided to transfer the weight of

the unit to the nearest beams. Figures 1 and 2

indicate the base plan for the chiller. Refer to

310VING AND PLACING THE UNIT, Page

foundation information.

additional structural mem-

9,

for

INSPECTION

When the equipment is received, all items should
be carefully checked to make sure that all crates and
cartons have been received. All units should be
carefully

damage should be reported immediately to the carrier
and a claim filed for damage.

inspected for damage when received. All

HANDLING

Every model PWA Seasonpak with water cooled
condensers (Arrangement
refrigerant charge. A holding charge is supplied in
condenserless models (Arrangements 2
shipment, the charge is contained in the condenser
and is isolated by the manual condenser liquid
valve and the compressor discharge service valve.

Should the unit be damaged allowing the refrigerant
to escape, there may be danger of suffocation in
the equipment area since the refrigerant will dis­place the air. Care should be taken to avoid rough
handling or shock due to dropping the unit. NEVER

LIFT, PUSH OR PULL UNlT FROM ANYTHING
OTHER THAN THE BASE. Refer to MOVING AND

PLACING UNIT, Pages 7
and 4 for further information.

1)

is supplied with a full

& 3).

thru

9, and Figures 3

For

SPACE REQUIREMENTS FOR
CONNECTIONS AND SERVICING

Dimensions of the unit are given in Figures 1 and

A.

2.

The chilled water piping for all units enters and

B.

leaves the cooler from the rear. A clearance of
2-3 feet should be provided for this piping and for
replacing the filter-driers or servicing the solenoid
valves.

The condenser water piping enters and leaves the

C.

shell from the ends. Work space must be provided

in case water regulating valves are being used and

for general servicing.

It is desirable to leave a small walk area on the

D.

end opposite that used for replacement of a cooler

tube. Figures 1 and 2 indicate the requirements

for

tube

replacement. Clearance for removing a
length of tube is required on one end only. The
cooler

tube is longer than the condenser, therefore,

the condenser tube replacement area need not

be considered.

ELECTRICAL

Simple three lead connection is all that is required
to connect power to the Seasonpak. Wiring should
conform with all local and national codes. The system
nameplate
with the power supply available. Check Electrical

section,

should be checked to be sure that it agrees

Pages

12 to 18, for further information.

WATER TEMPERATURE LIMITS

A. The maximum allowable water temperature to the

cooler must not exceed

stance, such as change over from heating to cool-

ing.

B. These units must not be operated when the enter-

ing water temperature is in excess of 90” F.

140’

F under any circum-

Page

4

MOVING ANDPLACING UNIT

MOVING THE UNIT

The light weight of the Seasonpak makes moving

A.

a simple matter. The

McQuay

Seasonpak is skidded
to protect the unit from being accidentally damaged
from any angle. Table 3 gives the approximate skid
dimens ions.

When moving the unit, dollies or simple pipe rollers

B.

can be used under the skid or under the base.
Always apply pressure to the base and not to the
piping or shells. A long bar helps move the unit
easily. Avoid dropping the unit at the end of the
roll.

The

4"

C.

channel base is arranged on the skid so

that the fork of a standard fork lift truck can be

slid easily under (See Figure

3).

The forks of the

fork lift truck must be across both the front and
rear channels before lifting. Always use a fork
lift truck on the side opposite the control panel to
avoid damaging the controls. Never put the weight
of the unit against the condensers.

If the unit must be hoisted, it is desirable to lift

D.

from the skid or from the base as indicated in

Figure 4, Page 8. A spreader bar must be used
to protect the control cabinet and other areas of
the chiller.

Do not attach slings to piping or equipment. Move

E

unit in the upright horizontal position at all times.
Let unit down gently when lowering from
or off

rollers.

TABLE 3

OVERALL SHIPPING

the truck

SKID DIMENSIONS

MODEL

PWA008

PWAOlO
PWAOlS

PWA020
PWA025

PWAOSO

PWA041 121

PWA050 128

PWA060 128

LENGTH WIDTH

98
98

98
121
121
121

39
39
39
34
34

38%

38%
40’/,
40’4

FIGURE 3

MOVING UNIT WITH FORK LIFT

THE CONTROLS.

Page 7

MOVING AND PLACING UNIT

FIGURE 4

SUGGESTED RIGGING

Page

*--

PLACING THE UNIT

The small amount of vibration normally encountered
with the Seasonpak makes this unit particularly
able for basement or ground floor installations where
the unit can be bolted directly to the floor. The floor
construction should be such that the unit will not af­fect

the building structure, or transmit noise and
vibration into the structure. See VIBRATION ISOLA­TORS section for additional mounting information.
Hold down bolt locations are indicated in Figures 1
and 2, Page 5.

VIBRATION ISOLATORS AND

ELIMINATORS

A.

Rubber-in-shear or spring isolators can be fur- C
nished and field placed under each corner of the
package. It is recommended that a rubber-in-shear

8

desir-

NOTE: ALWAYS USE SPREADER

BARS TO PROTECT UNIT
FROM DAMAGE.

pad be used as the minimum isolation on all upper
level installations or areas in which vibration
transmission is a consideration.

B. Transfer the unit as indicated under MOVING THE

UNIT, or use the methods as indicated in Figures
3 and 4. In all cases, set the unit in place and
level with a spirit level. When spring type isolators
are required,
main side channels as shown in Figure 5. Founda­tion hold down bolt locations for vibration isolators
are given in Figure 6. A rubber-anti-skid pad should
be standard under isolators if hold down bolts are
not used.

Vibration eliminators in all water piping connected
to the Seasonpak are recommended to avoid strain­ing the piping and transmitting vibration and noise.

install springs running under the

WATER

PIPING

GENERAL

A.

Piping practices

codes. local ordinances and established practices
govern the selection and installation of piping.
Local building and safety codes and ordinances
should be studied and complied with.

Shut off valves should bc provided at the unit so

B.

that normal servicing can be accomplished without
draining the system.

It is recommended that temperature and pressure

c

indicators be installed at the inlet and outlet of

the

shclls’to aid in the normal checking and

vicing

of the unit. Also. the installation of wire
mesh strainers at the pump suction will protect
the pump and shells from foreign matter.

A

preliminary leak check of the water piping should

D.

be made before filling the system.
Vibration eliminators are recommended in all lines

E.

connected to the Seasonpak.

vary considerably.

In most cases

CHILLED WATER PIPING

A.

Each cooler is provided with the connections as

indicated in Figures 1 and 2, Page 5. Also, a

NPT vent and S/4” NPT drain are provided.
Design

B.

the piping so that it has a minimum number
of changes in elevation. Include manual or auto­matic vent valves at the high points of the chilled
water piping, so that air can be vented from the

water circuit. System pressures can be maintained
by using an expansion tank or a combination pres­sure relief and reducing valve.

ser-

114”

C.

All chilled water piping should be insulated to
prevent the nuisance of water dripping from the

lines.
vapor barrier type,it should be covered with a
moisture seal. Do not insulate piping until it has
been tested for leaks and until all vent and drain
connections have been extended beyond the pro-

posed insulation thickness to make them
accessible.

The chilled water thermostat is mounted inside

D.

the control console, and the control bulb, capillary
tubing.and control bulb immersion well are at­tached to the unit with spring clips. The control

bulb well must be field inserted in the first tee

installed in the return water line as shown in

Figure 7. The bulb well is supplied with a

NPT male thread. Carefully unsnap the well from
the

and slowly remove the bulb from the well. Install

into piping as indicated in Figure
the bulb, carefully remove it from the well so as
to not wipe off the heat conducting compound sup­plied in the well. After installing the well, care­fully insert the bulb and seal in with the excess

compound. Insert the retaining gasket and sealing
bushing and clip or tape the cap tube to the water

line. Care should be taken not to break or kink the
charged capillary tubing. Sufficient cap tube length

is provided for bulb insertion up to
unit; however, it is recommended that the bulb well
be placed as close to the cooler inlet as possible.
Insulate over thermostat well.

CAUTION: The thermostat bulb should not be

posed to water temperatwes above
will

If insulation is not of the self-contained

holding clips, remove the retaining bushing

7.

When installing

10

feet from the

140 F

since this

damage the control.

112”

ex-

Page 10

FIGURE 7 THERMOSTAT WELL

RETURN WATER

TO

COOLER

INSTALLATION

‘/I”

N.P.T.

BUSHING

(BY

OTHERS)