15
Fig. 6 — Preferred Suspension Technique
Refrigerant Piping
See Tables 1-6 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 10 for part numbers. Knockouts
are provided in the unit corner posts for 40RU refrigerant piping.
See Fig. 7, which also lists recommended knockouts and access
holes to use for each 40RU unit size. Recommended fittings are
listed in Table 11.
The sensor bulb capillary tubes must be routed from the TXVs in
-
side 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. 8.)
Refrigerant and Chilled Water Piping Access
The 40RU Series units come with standard knockouts for refriger
-
ant 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, and 16 and 40RUQ*07, 08, and 12 units. 40RUQ*16 units,
as well as 40RUS*08, 12, 14, and 16 units require additional holes
that must be field-fabricated to accommodate the piping. See
Fig. 7 for the positions and dimensions of the additional access
holes required for 40RUQ*16 and 40RUS units. Recommended
access hole use is also listed for all units. Note that
Fig. 7 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.
NOTE: Be sure to remove the styrofoam shipping pad from the
TXV. Verify that it has been removed. (See Fig. 4.)
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. 9.)
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. 10.)
NOTE: Dimensions in [ ] are millimeters.
UNIT SIZES 07 - 12
OVERHEAD SUSPENSION ACCESSORY
UNIT SIZES 14 - 16
IMPORTANT: Never attach the sensor to the suction manifold.
Do NOT mount the sensor on a trapped portion of the suction
line.
