Section 18. Pressure Curves
PRESSURE CURVES (Refer below table for models)
LIQUID PRESSURE (PSIG)
OUTDOOR TEMPERATURE (Degree F)
SUCTION PRESSURE (PSIG)
OUTDOOR TEMPERATURE (Degree F)
COOLING PERFORMANCE CAN BE CHECKED WHEN THE OUTDOOR TEMP IS ABOVE 65 DEG F.
TO CHECK COOLING PERFORMANCE, SELECT THE PROPER INDOOR CFM, ALLOW PRESSURES TO STABILIZE. MEASURE INDOOR WET BULB
TEMPERATURE, OUTDOOR TEMPERATURE, LIQUID AND SUCTION PRESSURES. ON THE PLOTS LOCATE OUTDOOR TEMPERATURE (1);
LOCATE INDOOR WET BULB (2); FIND INTERSECTION OF OD TEMP. & ID W.B. (3); READ LIQUID (4) OR SUCTION (5) PRESSURE IN LEFT COLUMN .
EXAMPLE: (1) OUTDOOR TEMP. 82 F.
(2) INDOOR WET BULB 67 F.
(3) AT INTERSECTION ACTUAL:
(4) LIQUID PRESSURE @ 600 CFM IS 286 PSIG LIQUID PRESSURE SHOULD BE +/- 10 PSI OF CHART
(5) SUCTION PRESSURE @ 600 CFM IS 143 PSIG SUCTION PRESSURE SHOULD BE +/- 3 PSIG OF CHART
110
115
120
125
130
135
140
145
150
155
160
165
170
40 50 60 70 80 90 100110 120
170
220
270
320
370
420
470
520
40 50 60 70 80 90 100110 120
(1)
(1)
(3)
(3)
(5)
(4)
(2)
(2)
INDOOR ENTERING
WET BULB CURVES
TOP TO BOTTOM
71, 67, 63 AND 59 DEG F.
INDOOR ENTERING
WET BULB CURVES
TOP TO BOTTOM
71, 67, 63 AND 59 DEG F.
OD Model
4TTX5018N1
Cooling
@SCFM
600
71
67
63
59