Trane 4TWA3 Location and Preparation Unit, Installing Refrigerant Lines, Service Valve Operation

Installer’s Guide

2BASEPAN TAB REMOVAL

the sides of the unit and should be of sufficient distance from the unit to prevent restriction of airflow to and from the unit. Also allow for proper maintenance space. The barrier should be constructed of materials which will blend in with the building design.

3.Avoid locating the unit where condensation and freezing of defrost vapor may annoy the customer. For instance, installing the unit under a bedroom, kitchen, or picture window may be annoying to the customer since conden- sate and fog will occur during the defrost cycle.

4.Avoid locating the unit under the eaves or other overhead structures as sizeable icicles may form and the unit may be damaged by these falling icicles.

B. LOCATION AND PREPARATION

OF THE UNIT

1.When removing unit from the pallet, notice the tabs on the basepan. Remove tabs by cutting with a sharp tool as shown above in Figure 2, and slide unit off of pallet.

2.The unit should be set on a level support pad at least as large as the unit base pan, such as a concrete slab. If this is not the application used please refer to application bulletin “Trane XR-APG**-EN” (* denotes latest revision number).

3.The support pad must NOT be in direct contact with any structure. Unit must be positioned a minimum of 12" from any wall or surrounding shrubbery to insure adequate airflow. Clearance must be provided in front of control box (access panels) and any other side requiring service access to meet National Electrical Code. Also, the unit location must be far enough away from any structure to prevent excess roof run-off water from pouring directly on the unit. Do not locate unit(s) close to bedroom(s).

4.The top discharge area must be unrestricted for at least five (5) feet above the unit.

5.When the outdoor unit is mounted on a roof, be sure the roof will support the unit’s weight. Properly selected isolation is recommended to prevent transmission to the building structure.

6.The maximum length of refrigerant lines from outdoor to indoor unit should NOT exceed sixty (60) feet.

7.If outdoor unit is mounted above the air handler, maxi- mum lift should not exceed sixty (60) feet (suction line). If air handler is mounted above condensing unit, maximum lift should not exceed sixty (60) feet (liquid line).

8.Locate and install indoor coil or air handler in accordance with instruction included with that unit.

C. INSTALLING REFRIGERANT LINES

!CAUTION

If using existing refrigerant lines make certain that all joints are brazed, not soldered.

Condensing units have provisions for braze connections.

Pressure taps are provided on the service valves of outdoor unit for compressor suction and liquid pressures.

The indoor end of the recommended refrigerant line sets may be straight or with a 90 degree bend, depending upon situation requirements. This should be thoroughly checked out before ordering refrigerant line sets.

The gas line must always be insulated.

!CAUTION

In scroll compressor applications, dome temperatures may be hot. Do not touch top of compressor, may cause minor to severe burning.

The units are factory charged with the system charge required when using fifteen (15) feet of rated connecting line. Unit nameplate charge is with twenty-five (25) feet of line set.

Final refrigerant charge adjustment is necessary. Use the Charging Information in the outdoor unit Service Facts and on page 6.

1.Determine the most practical way to run the lines.

2.Consider types of bends to be made and space limitations.

NOTE:

Large diameter tubing will be very difficult to rebend once it has been shaped.

3.Determine the best starting point for routing the refriger- ant tubing — INSIDE OR OUTSIDE THE STRUCTURE.

4.Provide a pull-thru hole of sufficient size to allow both liquid and gas lines.

5.Be sure the tubing is of sufficient length.

6.Uncoil the tubing — do not kink or dent.

7.Route the tubing making all required bends and properly secure the tubing before making connections.

8.To prevent a noise within the building structure due to vibration transmission from the refrigerant lines, the following precautions should be taken:

a.When the refrigerant lines have to be fastened to floor joists or other framing in a structure, use isolation type hangers.

b.Isolation hangers should also be used when refriger- ant lines are run in stud spaces or enclosed ceilings.

c.Where the refrigerant lines run through a wall or sill, they should be insulated and isolated.

d.Isolate the lines from all ductwork.

D. SERVICE VALVE OPERATION

BRASS LIQUID LINE SERVICE VALVE

The Brass Liquid and Gas Line Service Valves are factory shipped in the seated position to hold factory charge. The

3LIQUID LINE SERVICE VALVE

© 2006 American Standard Inc. All Rights Reserved 18-BC62D1-1