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outlet can be changed if necessary. This is accomplished by detaching the shuttle
valve from the tower and reassembling it with the desired orientation.
The inlet for the
PMD model
(and the TOC model without a cabinet)
is the brass fitting
fastened to the bottom of the 4-way valve, and the outlet is the brass fitting in shuttle
valve at the top of the unit. The word “OUT” is inscribed in the shuttle valve body. The
inlet of the standard
TOC model
, is the filter on the left side of the cabinet (as you face
the front of the unit). The outlet is on the right side of the filter-regulator body.
All ports on the
PHF, PCDA, PHCA and PCME models
are ¼” female NPT, while the
PCR model
ports are ½” female NPT. The ports on the
PMD and TOC models
are
typically 1/8” female NPT, although ¼” NPT is optional with the cabinet. Use Teflon tape
or pipe sealant on all threaded connections. Prior to putting the unit into service, it is
advisable to check air connections for leakage by applying a diluted soap solution. If
tubing is used, be sure it has low moisture permeation and a sufficient pressure rating.
A bypass line is optional. It should be installed, however, if the application requires
constant airflow while the dryer or adsorber is being serviced. Moreover, adding an
inline scrubber to this bypass line will protect the downstream application while the dryer
or adsorber is being serviced. Electrically controlled shut-off valves and check valves
should also be employed as needed to prevent air from entering the de-energized unit.
Inlet and Outlet Filtration
Appropriate inlet filtration is mandatory for all models. Particles of dirt, rust or scale, as
well as condensed moisture and oil, are readily adsorbed by the desiccant, but cannot
be purged during the regeneration cycle. Thus, these solid and liquid contaminants will
significantly deteriorate the product’s performance and shorten it useful life.
For most compressed air sources, both a 5-micron particulate filter and a 0.01-micron
coalescing filter are recommended to optimize performance and extend maintenance
intervals. If the compressed air source is of instrument grade quality, the coalescing
filter by itself will usually offer sufficient protection. In both cases, the filters should have
automatic drains to avoid the frequent maintenance required by manually drained filters.
Outlet filtration is recommended for many applications. A 5-micron filter, installed at the
outlet of the dryer or adsorber, will effectively remove any desiccant dust that may
migrate from the desiccant chambers over time. PUREGAS offers an outlet filter, with
an integrated pressure regulator and gauge, for all models.
Pressure and Flow Control
Some means of regulating pressure and flow is required for nearly every application.
This should always be done AFTER the dryer or adsorber. Pressure and flow regulation
is especially important for applications near atmospheric pressure. As previously
stated, PUREGAS offers an outlet filter-regulator for all models, as well as a flow meter
with a built-in flow control valve. For those applications especially sensitive to pressure
