Installation and Maintenance Manual

UV-SVN02C-EN 23
Installation—Piping
Note: Before installation of piping package, the shipping
bracket holding the piping in place, must be
removed.
Proper installation of piping is necessary to provide
efficient coil operation and to prevent damage during
operation. Follow standard piping practices and include all
accessories as necessary.
Piping connection knockouts are shown in Figure 5, p. 13
through Figure 9, p. 17. Field connection types and sizes
for units without piping packages are listed in Ta b l e 10,
p. 23.
A 3/4-in. OD condensate drain connection is provided on
the chilled water supply end of the unit. Attach a flexible
condensate drain hose over the drain pan connection and
secure with a hose clamp.
The drain pan on the horizontal unit is internally pitched.
To field reverse, remove the screws and drain pan, rotate
the pan and reinstall.
After the condensate drain piping has been completed,
check water flow to be sure the system properly carries and
away all condensate accumulation.
A P-trap is recommended for installations that drain
directly into a sewer system. A P-trap is not necessary for
operation but will eliminate sewer gas odor.
Trane Piping Packages (Option)
Trane Standard Piping Package includes a two- or three-
way valve with bypass balance valve, ball valves, Pete’s
plugs, and unions. A strainer and circuit balancing valve
are optional.
All union connections should be tightened in the field.
Units are shipped with union connections hand-tightened
only in the factory.
Notes:
• All connections made in the field should be sweat
connections.
• Piping packages are not shipped insulated. Any
insulation should be provided in the field by the
installing contractor.
Split System Units
The following refrigerant piping and interconnecting
wiring instructions apply to unit ventilators with direct
expansion type cooling coils used in conjunction with air-
cooled condensing units. Reference must also be made to
the condensing unit installation and wiring manuals which
are shipped with the condensing unit.
Note: A UL listing mark applied to a unit ventilator does
not apply to any associated refrigerant condensing
unit.
Refrigerant Piping
Unit ventilators with direct expansion cooling are
dehydrated and shipped with a dry air holding charge.
Connections are “pinched off” at the factory.
To connect the condensing unit lines, cut off the stubouts
and swage. The condensing unit lines can then be brought
into the swage and brazed. Trane recommends the use of
nitrogen purge when brazing refrigerant lines to prevent
formation of oxides in the lines.
Table 10. Coil data for field piping
Coil Type Connection Location Field Connection Size
4-pipe chilled water /
hot water
Left or right (opposite
ends)
7/8 in. OD / 5/8 in. OD
2-pipe changeover coil Left or right 7/8 in. OD
Hot water only Left or right 7/8 in. OD
Steam Left or right 1 in. MPT
Chilled water / electric
heat
Left cooling 7/8 in. OD
Chilled water / steam Left or right 7/8 in. OD / 1 in. MPT
DX Left 7/8 in. suction, 3/8 in.
DX / hot water Left cooling / right
heating
7/8 in. suction,
3/8 in. / 5/8 in. OD
DX / steam Left cooling / right
heating
7/8 in. suction,
3/8 in. / 1 in. MPT
DX / electric heat Left cooling / right
heating
7/8 in. suction,
3/8 in. / NA
Figure 14. Condensate drain pan location
13-5/8"
3"
Horizontal Unit
WARNING
Hazard of Explosion and Deadly Gases!
Never solder, braze or weld on refrigerant lines or any
unit components that are above atmospheric pressure
or where refrigerant may be present. Always remove
refrigerant by following the guidelines established by
the EPA Federal Clean Air Act or other state or local
codes as appropriate. After refrigerant removal, use dry
nitrogen to bring system back to atmospheric pressure
before opening system for repairs. Mixtures of
refrigerants and air under pressure may become
combustible in the presence of an ignition source
leading to an explosion. Excessive heat from soldering,
brazing or welding with refrigerant vapors present can
form highly toxic gases and extremely corrosive acids.
Failure to follow all proper safe refrigerant handling
practices could result in death or serious injury.
UV-SVN02_-EN.book Page 23 Thursday, January 24, 2013 4:48 PM