SEASONCON” Packaged air cooled condensing unit Models ALP-O16A thru -033A McQuay

REFRIGERANT PIPING

McQUAY type ALP SEASONCON condensing units are adaptable to either chilled water or air handling air conditioning applications using refrigerant 22. Refrigerant piping to and from the unit should be sized and installed according to the latest ASHRAE Guide. The following discussion is for use as a general guide to sound, economical and trouble-free piping. The correct application of the principles discussed here is the responsibility of the installer.

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. Evaporator Above Condensing Unit

-G-AIR F L O W

EVAPORATOR BELOW CONDENSING UNIT

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 required for shell-and-tube evaporators. Note that a double suction riser is shown for this arrangement.

Risers

“A + B” are sized so that their combined cross-sectional internal 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.

This riser becomes effective only when the trap shown in riser “A” fills itself with oil. It should be emphasized that the trap shown in riser “A” 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.

FIGURE 7. Evaporator Below Condensing Unit

LEGEND a

F i l t e r d r i e r b Solenoid valve c Sightglasslmoisture indicator d Thermal expansion valve e Suction line, pitched toward compressor f Liquid line g Vibration absorber

NOTES: All piping and piping components are by others.

TABLE 4.

ALP RECOMMENDED LINE SIZE

UNIT DOUBLE

SIZE

+y;.?l

SINGLE

SUCTION

LIQUID

016A-S

1 118-l l/8 1 518 718

019A-S 1 318-l 318 2 118 718

023A-S 1 518-l 318 2 118 1 l/8

027A-S 1 518-l 318 2 118 1 l/8

033A-S 1 518-l 518 2 118 1 118

Note: Liquid and suction lines based on a recommended pressure drop of 3 PSIG 12OF) per 100 ft. equrvalent length.

e-AIR F L O W

LEGEND a F i l t e r d r i e r b Solenoid valve c Sightglass/moisture indicator d Thermal expansion valve e Suction line, pitched toward compressor f Liquid line g Vibration absorber

A+8 - Double suction riser (see note 2)

NOTES:

1. All piping and piping components are by others.

2. Trap for double suction riser should be as small in the horizontal direction as fittings will allow.

REFRIGERANT PIPING CONNECTIONS

Refrigerant piping connections should be made through the holes provided in the base frame on access screen side of the unit.

PAGE 5

LIQUID LINE COMPONENTS

McQUAY

has available a “Liquid Line Accessory Kit” for each ALP unit size. Table 5 shows the ordering number to be used for each ALP unit size. The components included in these kits are:

1.

4:

5.

Replaceable core type filter-drier.

Filter-drier core element.

Refrigerant solenoid valve.

Refrigerant sightglass/moisture indicator.

Expansion valve.

TABLE 5. LIQUID LINE ACCESSORY KITS

,

ALP LIQUID LINE CONNECTION SIZES O.D. (IN.1

U N I T ACCESSORY KIT FILTER- S O L E N O I D SIGHT- EXPANSION VALVE

SIZE ORDERING NUMBER D R I E R V A L V E G L A S S I N O U T

016A-S 886-368903641

019A-S 8 8 6 3 6 6 9 0 3 6 4 1

718

718

718

7/a

7ta

7/a

718

7/a

I

318 i

3/a

023A-S

027A-S

033A-S

8863689039-01

886-368903841 aa6-36890384x2

718

7/a

7ta

718

7/a

718

718

7/a

718

718

718

718

I

3/a i

318 i

3/a

FIGURE 8. DIMENSIONAL DRAWING

REFRIGERANT CHARGE ADDING REFRIGERANT CHARGE

Each ALP condensing unit is designed for operation using refrigerant 22. Table 6 lists refrigerant charge required for a condensing unit/cooler combination.

TABLE 6. APPROXIMATE REFRIGERANT CHARGE

O n s y s t e m s t h a t h a v e b e e n previously c h a r g e d w i t h 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.

ALP ‘R-22 REFRIGERANT

M O D E L CHARGE (LBS.)

016A-S 17

019A-S 23

023A-S 32

0 2 7 A S 37

033A-S 53 l

Refrigerant

charge is for a close-coupled system. A remote cooler will require an additional charge.

CAUTION: Do not make any safety controls inoperative during the charging operation: cooler damage from freezing may result.

1. Back seat the liquid line shut-off valve and connect the charging hose to the 1/4-inch flare connectron.

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.

PAGE 6