Daikin McQuay AGZ-D, Operating And Maintenance Manual, Page: 70 / 82

70 AGZ 025D through 190D OMM 1087
The evaporator is protected with an electric resistance heater and insulated with 3/4" (19mm) thick
closed-cell polyurethane insulation. This combination provides freeze protection down to -20°F (-
29°C) ambient air temperature.
The water side working pressure is 363 psig (2503 kPa). Evaporators are designed and constructed
according to, and listed by, Underwriters Laboratories (UL).
NOTE : This product is equipped with a copper-brazed series 304 stainless steel plate evaporator. The
water or other fluid used in these evaporators must be clean and non-corrosive to the materials used in
the evaporator. The use of non-compatible fluids can void the equipment warranty. If the compatibility
of the fluid with the evaporator is in question, a professional water quality consultant should administer
the proper testing and evaluate compatibility.
Models AGZ 140C through 180C
The evaporator is direct expansion, shell-and-tube type with water flowing in the baffled shell side and
refrigerant flowing through the tubes. Two independent refrigerant circuits within the evaporator serve
the unit's dual refrigerant circuits.
The evaporator is wrapped with an electric resistance heater cable and insulated with 3/4" (19mm)
thick vinyl nitrate polymer sheet insulation, protecting against water freeze-up at ambient air
temperatures to -20°F (-29°C). An ambient air thermostat controls the heater cable. The fitted and
glued-in-place insulation has a K factor of 0.28 Btu in/hr ft
2 
F at 75°F.
The refrigerant (tube) side maximum working pressure is 300 psig (2068 kPa). The water side working
pressure is 152 psig (1048 kPa). Each evaporator is designed, constructed, inspected, and stamped
according to the requirements of the ASME Boiler and Pressure Vessel Code. Double thickness
insulation is available as an option.
Phase Voltage Monitor (Optional)
Factory settings are as follows:



Trip Delay Time, 2 seconds



Voltage Setting, set at nameplate voltage.



Restart Delay Time, 60 seconds