![background image](http://html1.mh-extra.com/html/carrier/40rum-series/40rum-series_installation-operation-and-maintenance-manual_2561997009.webp)
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 Piping Access –
The 40RUM Series units come with standard knockouts for refrigerant. 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 40RUM units. Recommended access hole use is also listed for all units. Unit
Dimensional Drawing 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.
The 40RUM direct-expansion units have internal factory--installed thermostatic expansion valves (TXVs),
distributors, and nozzles for use with R-410A. Knockouts are provided in the unit corner posts for 40RUM refrigerant
piping. See Unit Dimensional Drawing, which also lists recommended knockouts and access holes to use for each
40RUM unit size. Recommended fittings are also listed.
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.
Face-Split Coil Suction and Liquid Line Piping (Typical)
LEGEND:
TXV – Thermostatic Expansion Valve
NOTE: Component location arrangement shown for field installation of sight glasses, solenoid valves, filter driers, and
TXV sensing bulbs. The TXVs and equilizer lines are factory installed.
Typical Evaporator Coil Connections (40RUM) TXV Sensing Bulb Location
Single Circuit Coil Piping Configuration RUM 07, 08
For single compressor condensing units.
Dual Circuit Coil Piping Configuration RUM 10 - 16
For single compressor condensing units.
Page 9