JOHNSON CONTROLS
18
FORM 160.69-N3
ISSUE DATE: 10/30/2015
SECTION 2 - INSTALLATION
REFRIGERANT RELIEF PIPING
Each unit is equipped with pressure relief valves lo-
cated on the condenser and on the evaporator for the
purpose of quickly relieving excess pressure of the re-
frigerant charge to the atmosphere as a safety precau-
tion in case of an emergency, such as fire.
Refrigerant relief vent piping (by others), from the re-
lief valves to the outside of the building, is required
by code in most areas and should be installed on all
chillers. The vent line should be sized in accordance
with the ANSI/ASHRAE-15, or local code. The vent
line must include a dirt trap in the vertical leg to in-
tercept and permit clean out and to trap any vent stack
condensation. The piping MUST be arranged to avoid
strain on the relief valves, using a flexible connection,
if necessary.
FIGURE 10 -
TYPICAL REFRIGERANT VENT PIPING
FLANGED JOINT
TO PERMIT PIPING
DISASSEMBLY
CONDENSATION
TRAP
DUAL RELIEF
VALVES
VENT TO ATMOSPHERE
SUPPORT VENT PIPING TO AVOID
STRAIN ON RELIEF PIPING
FLEXIBLE CONNECTOR
CONDENSER
EVAPORATOR
SEE NOTE
NOTE: SHELLS MAY BE FURNISHED WITH
ONE OR TWO RELIEF VALVES,
DEPENDING ON SHELL SIZE.
LD03863
When installing relief piping there
must NOT be any piping strain.
Relief piping must be properly
aligned and supported to eliminate
any possible piping strain.
When installing relief piping an
ANSI flange or a piping union
must be used to make a
servicable piping connection.
Horizontal
Mis-aligned
Vertical
Offset
Compressed
LD16677