12
McQuay IM 777-2
Installation Guidelines
Figure 19: Piping Arrangements
Vacuum breaker
1/2" check valve
Steam main
1/4" petcock
for continuous
air venting
High pressure
float or bucket
trap
Return main
1"
min.
12" min.
Vacuum breaker
1/2" check valve
Steam main
1/4" petcock
for continuous
air venting
High pressure
bucket trap
Return main
1" min.
12" min.
Full size of
return conn.
Vacuum breaker
1/2" check valve
Steam main
Return main
Vacuum breaker
1/2" check valve
Steam main
Return main
12" min.
Vacuum breaker
1/2" check valve
Steam main
Return main
12" min.
Full size of
return conn.
Check Valve
Strainer
Gate Valve
Control valve
modulating
two position
Float and
thermostatic trap
High Pressure (over 25 psi)
Low Pressure (to 25 psi)
5GA or 8GA coils.
Note that the
addition of a vacuum breaker to
permit the coil to drain during
shutdown.
5TA, 8TA, or 5HA coils.
Conden-
sate is lifted to overhead return
main
5JA or 8JA coil.
Installed in series.
Note that each coil must have a
separate control valve and trap.
5RA, 8RA, or 5SA coils.
Banked two
high, individual trapping of each coil as
shown is preferred.
5RA, 8RA, or 5SA coils.
Installed
5J, 5G, 8J or 8G coils.
