Carrier 40RU User Manual

Page 13

Unit Isolation -- Where extremely quiet operation is

essential, install isolators between floor and base of unit,

or between ceiling and top section of unit.

Be sure that unit is level and adequately supported. Use

channels at front and sides of unit for reference points

when leveling.

Refrigerant and Chilled Water Piping Access -- The

40RU Series units come with standard knockouts for

refrigerant and chilled water piping. These knockouts are

located on both sides of the unit for installation flexibility.

The standard knockouts provide sufficient access to the

unit’s coils for all 40RUA*07, 08, 12, 14, 16 and

40RUQ*07, 08, 12 units. 40RUQ*16 units, as well as

40RUS*08, 12, 14, and 16 units require additional holes

which must be field--fabricated to accommodate the

piping. See Fig. 8 for positions and dimensions of the

additional access holes required for the 40RUQ*16 and

40RUS units. Recommended access hole use is also listed

for all units. Note that Fig. 8 shows the access holes on

the control--box side of the unit; this is the side of the unit

with the coil headers, so it is used most often for piping

access.
IMPORTANT: Do not bury refrigerant piping underground.
Refrigerant Piping -- See Tables 1A–1F for refrigerant

pipe connection sizes. For ease in brazing, it is

recommended that all internal solder joints be made

before unit is placed in final position.

The

40RU

direct--expansion

units

have

internal

factory--installed thermostatic expansion valves (TXVs),

distributors, and nozzles for use with R--410A. See Table 2

for part numbers. Knockouts are provided in the unit corner

posts for 40RU refrigerant piping. See Fig. 8, which also

lists recommended knockouts and access holes to use for

each 40RU unit size. Recommended fittings are listed in

Table 3.

The sensor bulb capillary tubes must be routed from the

TXVs inside the unit through one of the piping access

holes. Clamp the TXV sensor bulb on a vertical portion of

the suction line, outside the unit. See Fig. 9.
NOTE: Be sure to remove the styrofoam shipping pad
from the TXV. Verify that it has been removed. See Fig. 5.
IMPORTANT: Never attach the sensor to the suction

manifold. Do NOT mount the sensor on a trapped portion
of the suction line.
The 40RU Series evaporator coils have a face--split design.

Ensure that lower circuit of coil is first on/last off when

connected to the condensing unit and/or system controls. See

Fig. 10.

External TXV equalizer connections are provided and

factory--brazed into the coil suction manifolds.

If suction line must be horizontal, clamp bulb to suction

line at least 45 degrees above bottom, at approximately

the 4 o’clock or 8 o’clock position. See Fig.11.

3
2

7
6
5

C10686

UNIT

USE HOLE

NUMBERS

FIELD---FABRICATED HOLE DIAMATERS

in. (mm)

FIELD---FABRICATED HOLE POSITION

DIMENSIONS, in. (mm)

No. 5

No. 6

No. 7

40RUA*07, 08

40RUQ*07, 08

1, 3

—

40RUA*12, 14, 16

40RUQ12

1, 2, 3, 4

—

40RUS*08, 12

4, 5

(44.5)

—

6.25 (158.8)

—

40RUS*14, 16

4, 5, 6, 7

(44.5)

3.0 (76.2)

6.0 (152.5)

10.5 (266.7)

40RUQ*16

{

, 5, 6, 7

/8 (28.6)

(44.5)

3.25 (82.6)

6.125 (155.6)

10.38 (263.7)

{

Must be enlarged from 1

in. (28.6mm) to 1

in. (44.5mm)

NOTE: Access hole knockouts 1--- 4 are factory--- supplied.

Fig. 8 -- Refrigerant and Chilled Water Piping Access Holes

40RU