Section 18. Pressure Curves - Trane 4TTA4 Installation And Operation Manual

Section 18. Pressure Curves

500
450
400
350
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145
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120
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
(4) LIQUID PRESSURE @ 600 CFM IS 309 PSIG
(5) SUCTION PRESSURE @ 600 CFM IS 142 PSIG
18-AC108D1-1D-EN
PRESSURE CURVES (Refer below table for models)
INDOOR ENTERING
WET BULB CURVES
TOP TO BOTTOM
71, 67, 63 AND 59 DEG F.
(3)
(4)
50 60 70 80
OUTDOOR TEMPERATURE (Degree F)
INDOOR ENTERING
WET BULB CURVES
TOP TO BOTTOM
71, 67, 63 AND 59 DEG F.
(5)
50 60 70
OUTDOOR TEMPERATURE (Degree F)
(1)
90 100 110
(3)
(1)
80 90 100 110
ACTUAL:
LIQUID PRESSURE SHOULD BE +/- 10 PSI OF CHART
SUCTION PRESSURE SHOULD BE +/- 3 PSIG OF CHART
(2)
OD Model
120
4TTA4036A3
4TTA4042A3
4TTA4036A4
4TTA4042A4
71
(2)
67
63
59
120
Cooling
@SCFM
1100
1300
1100
1300
29