Install Steam and Condensate Piping —
Figure 14 shows a typical piping schematic. Refer to job data
and certified drawings for data specific to your installation.
1. Make sure connections to the steam box cover (see
Fig. 5 and 6) allow for removal of the cover for
maintenance.
2. Install pipe hangers where needed. Make sure no weight
or stress is placed on the steam chest cover (see Fig. 5
and 6), nozzle, or on the condensate drain connection.
3. Locate the capacity control steam valve at least
3 ft (1 m) from the generator nozzle. For inspection and
maintenance, a bypass line with a manual valve (Fig. 14,
Item V1) should be installed around the capacity control
valve. Also, a manual shut-off valve (V2) should be in-
stalled ahead of the capacity control steam valve. Install
isolation valves (Fig. 14, Item V3 and V4) on the inlet
and outlet sides of the capacity control steam valve. Pip-
ing must allow for thermal expansion and slope slightly
toward the generator for condensate drainage.
4. Two pressure gages (Fig. 14, Items P6 and P7) with a
pressure range of 0 to 200 psig (0 to 1400 kPa) should be
installed before and after the capacity control steam valve.
5. If the primary steam supply pressure is above 125 psig
(862 kPa), install a steam pressure reducing valve be-
tween the primary steam supply and the capacity control
steam valve inlet (Fig. 14). Install a bypass valve around
the steam pressure reducing valve, a steam strainer on the
inlet side of the steam pressure reducing valve, and iso-
lation valves around the pressure reducing valve.
6. If the steam supply pressure to the generator can exceed
114 psig (786 kPa), a safety relief valve (Fig. 14, Item
V5) must be installed between the capacity control steam
valve and the generator to limit the pressure to 114 psig
(786 kPa). The safety relief valve should be vented to the
outside of the building for safety.
7. Install steam condensate drain piping so that the back pres-
sure at the connection to the chiller is less than
7 psig (48 kPa) to prevent condensate back-up into the
generator tubes at low load conditions. Include a check
valve (Fig. 14, Item V6) and manual shut-off valve
(Fig. 14, Item V7) at the condensate drain outlet.
Fusible Plug Drain Piping (Fig. 15) —
For 16JT
chillers with fusible plug drain piping:
1. Connect drain piping to discharge the hot refrigerant wa-
ter to a safe area.
2. Do not loosen or disconnect the fusible plug while con-
necting the relief pipe to it.
3. Make sure connections to the fusible plug are threaded
and allow easy pipe removal for leak tests and
maintenance.
4. Install pipe hangers where needed to be sure that no weight
or stress is placed on the fusible plug.
Rupture Disc Piping —
16JT chillers are factory
equipped with a rupture disc assembly on the condenser shell.
Chillers with fusible drain piping have a 2-in. rupture disc
(Fig. 15); chillers without fusible drain piping have a 3-in.
rupture disc (Fig. 16).
Vent rupture discs to the outside of the building for safety.
1. Add a flexible connection and adequate support to the pipe,
as required, to eliminate any piping stress on the rupture
disc. Provide fittings so vent piping can be disconnected
periodically for inspection of the disc. Provide a pipe plug
on the outlet side of the relief device for leak testing.
2. Cover the outdoor vent with a rain cap to prevent exces-
sive moisture from entering the vent line.
3. Place a condensate drain at the low point in the piping to
prevent water build-up on the atmospheric side of the disc
assembly.
*R.F. — Raised Face.
Fig. 15 — Rupture Disc Location on Chillers With a
Fusible Plug
*R.F. — Raised Face.
Fig. 16 — Rupture Disk Location on Chillers
Without a Fusible Plug
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