33
Application data
Operating limits
Maximum operating temperature . . . . . . . . . . . . . .115 F
Minimum return-air temperature . . . . . . . . . . . . . . .55 F
Maximum return-air temperature . . . . . . . . . . . . . . .95 F
Maximum outdoor-air operating
temperature in heating . . . . . . . . . . . . . . . . . . . .75 F
Minimum outdoor-air operating
temperature in heating . . . . . . . . . . . . . . . . . . . –20 F
Range of acceptable saturation suction
temperature . . . . . . . . . . . . . . . . . . . . . . . 25 to 55 F
Maximum discharge temperature . . . . . . . . . . . . . .275 F
Minimum discharge superheat . . . . . . . . . . . . . . . . 60° F
Maximum indoor unit fan speed. . . . . . . . . . . .1200 rpm
General
Select equipment to match or to be slightly less than peak
load. This provides better humidity control, less unit
cycling, and less part-load operation. Equipment should be
selected to perform at no less than 300 cfm/ton.
The indoor unit fan must always be operating when the
outdoor unit is operating.
Ductwork should be sized according to indoor unit size,
not building load. For larger units with two fans, a split duct
transition is recommended at the fan outlets, but a plenum
can be used with slight reduction in external static pressure
capability.
For variable air volume (VAV) systems with supply-to-
return air recycling, use the equipment room as a return air
plenum.
40RMQ
