PRESSURE CURVES FOR 4TWZ0060A1000A
1
A
0
1
C
3
E
E
T
4
1
A
0
1
C
3
E
E
T
4
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 INTERSECTION
ACTUAL:
(4) DISCHARGE PRESSURE @ 900 CFM IS 296 PSIG
DISCHARGE PRESSURE SHOULD BE +/- 10 PSI OF CHART
(5) SUCTION PRESSURE @ 1600 CFM IS 145 PSIG
SUCTION PRESSURE SHOULD BE +/- 3 PSIG OF CHART
INTERCONNECTING LINES
GAS - 3/4" O.D.
LIQUID - 3/8" O.D.
DWG.NO. 4TWZ0060A1000AA
200
250
300
350
400
450
500
550
40
60
80
100
120
115
125
135
145
155
165
175
185
40
60
80
100
120
115
125
135
145
155
165
175
185
40
60
80
100
120
40
50
60
70
80
90
100
110
120
130
140
150
160
-5 5 15 25 35 45 55 65
200
250
300
350
400
450
500
-5 5 15 25 35 45 55 65
40
50
60
70
80
90
100
110
120
130
140
150
160
-5 5 15 25 35 45 55 65
200
250
300
350
400
450
500
-5 5 15 25 35 45 55 65
Heating with Thermal Expansion Valve
INDOOR ENTERING DRY BULB CURVES TOP TO BOTTOM
80, 70, AND 60 DEG F.
200
250
300
350
400
450
500
550
40
60
80
100
120
Cooling with Thermal Expansion Valve
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.
INDOOR ENTERING DRY BULB CURVES TOP TO BOTTOM
80, 70, AND 60 DEG F.
OUTDOOR TEMPERATURE (Degree F)
D
IS
C
H
A
R
G
E
P
R
E
S
S
U
R
E
(
P
S
IG
)
S
U
C
T
IO
N
P
R
ESS
U
R
E
(PS
IG
)
OUTDOOR TEMPERATURE (Degree F)
2ND STAGE
2ND STAGE
1ST STAGE
1ST STAGE
2ND STAGE
2ND STAGE
1ST STAGE
1ST STAGE
(1)
(1)
(3)
(3)
(5)
(4)
(2)
(2)
8
