DUPLEX STACK MOUNTED SCROLL COMPRESSED
WITH DESICCANT DRYERS
Furnish and install, where
shown on the drawings a duplex stack
mounted prefabricated medical compressed air plant with desiccant air dryers model
3DOHS10PS120D-B as manufactured by EMSE Corporation,
The
unit furnished shall be a standard catalog item of the supplier regularly
engaged in the business of providing packaged systems for hospitals and
laboratories and shall meet and exceed the requirements of NFPA 99.
The
only field connections required will be system intake, exhaust and power
connection at the control panel. All components shall be completely pre-piped
and pre-wired to single-point service connections. All interconnecting piping
and wiring shall be completed and operationally tested prior to shipment.
Provide liquid tight conduit, fittings and junction boxes for all control and
power wiring.
The
medical air compressors shall be of the totally oil-less rotary scroll design.
They are dynamically balanced for very low noise levels and virtually no
vibration.
Each
compressor set shall be belt driven by a 10 HP, 3 phase,
60 cycle, ______ volt, 1750
The
NFPA system capacity with reserve compressor on stand-by shall be 34.8 CFM at
120 PSIG.
The
system shall include compressor inline intake filters, discharge check valves
of bronze construction, safety relief valves, bronze intake and discharge
flexible connectors, isolation valves, air cooled aftercoolers for each
compressor, high discharge temperature shut down switches, pressure control
switches, as well as copper tubing with shut-off cock for gauge and switches. The
system shall include a 120 gallon pressure storage tank of ASME construction
rated for 200
The
system shall include a UL listed control panel in a NEMA 12 enclosure with the
following accessories:
Externally
operable circuit breaker with door interlock, control circuit transformers with
fused primary and secondary coils, H-O-A switches, magnetic starters with 3 leg
overload protection, hour meters and motor running lights. Provide audible and
visual local alarm (complete with indicating lights and individual sets of
auxiliary contacts wired to the terminal strip for remote alarm indication) for
the following: compressor temperature malfunction and
reserve compressor in use. Provide manual reset for thermal malfunction
shut-down. All control and alarm functions shall remain energized while any
compressor in the system remains electrically on-line. The lag compressor set
shall be able to start automatically if the lead compressor set fails to
operate.
A
completely packaged NFPA 99 and NEC compliant assembly featuring dual desiccant
air dryers, dual 0.5 micron pre-filters, dual 0.5 micron after-filters, line
pressure regulating valves, dew point monitor, CO monitor and other accessories
required to meet and exceed the current code requirements shall be provided as
part of the receiver skid. All components shall be completely pre-piped and
pre-wired to single-point service connections.
There shall be two identical banks of air treatment equipment, piped in parallel and provided with valves to by-pass either filter set for element replacement, maintenance and repair work on one of the sets while still treating medical compressed air through the other set without any sacrifice in air quality. Each bank consists of three stages of treatment.
The first stage is a prime efficiency coalescer with
particle removal down to 0.5 micron with 99.9999% retention. This filter
removes aerosols and solid particles. The filter is equipped with electronic
drain and element change indicator.
The second stage is a desiccant heatless air dryer,
equipped with purge control. Pressure dew point of 0oF is attained by directing the flow of saturated
compressed air over a bed of desiccant which is contained in two separate but
identical "twin" towers. Built-in purge saver control will
automatically minimize and adjust the amount of purge air to match the variable
air flow. The dry compressed air is discharged from the "on line"
tower into the third stage.
The third stage is a prime efficiency particulate
afterfilter with particle removal down to 0.5 micron. The after filter element
is provides high particle retention, low pressure drop and long element life.
Downstream pressure regulators will maintain
constant discharge pressure of 55 PSIG (field adjustable).
Digital dew point and CO monitors with alarm set
points at +390F and 10 PPM are
provided with dry contacts for connection to remote alarm panels. A
"demand check" for maintenance is included per current NFPA 99 for
each instrument.
The
compressed air system shall be guaranteed in writing by the manufacturer for a
period of 12 months from the date of start-up or 18 months from the date of
shipment (whichever comes first) against defects in design, materials, or
construction. In addition, the compressors are guaranteed for 36 months from
the date of shipment.
The service of a factory trained representative shall
be made available at the jobsite to check installation, start-up and instruct
operating personnel in the proper operation and maintenance.