Product Manual AGZ-2
AGZ 030A through 065A
49
MicroTech microprocessor control with a 12 key keypad and 2-line, 16 character
backlit liquid crystal display operator interface. The controller shall continuously
perform self-diagnostic checks on all system temperatures, pressures, and safeties,
and automatically shut down a circuit or the entire unit at fault conditions. The
cause, time, and date of the occurrence shall be recorded and displayed along with
availability to view the seven previous incidents.
The controller shall take proactive measures to stay on-line for non-critical
abnormalities; staging down capacity, activating a pre-alarm signal and automatically
switching to the alarm menu on the display. These pre-alarms shall be self-clearing
when the off-condition is corrected.
Critical shutdown alarms such as high condenser pressure, freeze protection, and
low evaporator pressure shall be manual reset and cleared at the keypad to resume
operation. The leaving water sensor shsall be field install in the evaporator nozzle
and the cable field spliced if necessary.
E.
The refrigerant discharge pressure shall be controlled by a FanTrol system
that cycles condenser fans based on discharge pressure and shall be operational 40
°
F
(4.4
°
C).
- OR -
The refrigerant discharge pressure shall be controlled by a SpeedTrol control
employing both fan cycling and fan speed control and allow operation to
0
°
F (-18
°
C).
F.
Remote Evaporator: The evaporator shall be direct expansion, shell and tube with
carbon steel shell and high efficiency copper tubes rolled into steel tube sheets. Internal
baffles shall be polypropylene. The refrigerant heads shall have multi-pass baffles to insure
oil return and be removable to permit access to the tubes from either end. The shall be
insulated with 3/4 inch (19mm) closed cell polymer insulation with a minimum K factor of
0.28 at 75
°
F (23
°
C) and be heated (if located in below freezing temperature area) with an
electric heater to provide freeze protection to -20°F (-29°C) ambient temperature. The
refrigerant side working pressure shall be at least 225 psig (1552 kPa). The water side
working pressure shall be at least 175 psig (1207 kPa) The evaporator must be designed,
constructed, inspected, and stamped according to the ASME Code.
G.
Refrigerant Circuit: The condensing unit shall be furnished with factory mounted
liquid and suction shutoff valves. The field piped refrigerant circuit shall include a
refrigerant filter-drier, sight glass with moisture indicator, liquid line solenoid valve (no
exceptions), thermal expansion valve, and insulated suction line. The contractor shall submit
the piping design for approval. The piping shall be designed, installed, evacuated, and charged
according to accepted practice.
Summary of Contents for AGZ 030AM
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