Section 19. Pressure Curves - Trane 4TWR4 Installation And Operation Manual

Section 19. Pressure Curves

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, DISCHARGE 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 DISCHARGE OR SUCTION PRESSURE IN LEFT
COLUMN (4).
EXAMPLE: (1) OUTDOOR TEMP. 82 F.
(2) INDOOR WET BULB 67 F.
(3) AT INTERSECTIO
(4) DISCHARGE PRESSURE @ 670 CFM IS 318 PSIG.
(5) SUCTION PRESSURE @ 670 CFM IS 149 PSIG.
550
INDOOR ENTERING
WET BULB CURVES
TOP TO BOTTOM
500
71, 67, 63 AND 59 DEG F.
450
400
350
(4)
300
250
200
50
170
INDOOR ENTERING
WET BULB CURVES
165
TOP TO BOTTOM
71, 67, 63 AND 59 DEG F.
160
155
(5)
150
145
140
135
130
50
18-BC95D1-5E-EN
N
PRESSURE CURVES FOR 4TWR4017N1
TEM4A0B18S21+TDR
Cooling @ 670 SCFM
(3)
(1)
70 90 110
(3)
(1)
70 90 110
OUTDOOR TEMPERATURE (Degree F)
A CTUAL:
DISCHARGE PRESSURE SHOULD BE +/- 10 PSI OF CHART
SUCTION PRESSURE SHOULD BE +/- 3 PSIG OF CHART
500
INDOOR ENTERING
DRY BULB CURVES
(2)
TOP TO BOTTOM
450
80, 70, AND 60 DEG F.
400
350
300
250
200
-5 5
140
INDOOR ENTERING
130 DRY BULB CURVES
TOP TO BOTTOM
120 80, 70, AND 60 DEG F.
(2)
110
100
90
80
70
60
50
40
30
-5 5
TEM4A0B18S21+TDR
Heating @ 670 SCFM
15 25 35 45
15 25 35 45
55 65
55 65
25