Charging - Lennox HS29-072 Installation Instructions Manual

Charging

UNIT MODEL
NUMBER INDOOR UNIT
HS29 072 HS29−072 CB17/CBH17 95 CB17/CBH17−95
HS29 090 HS29−090 CB17/CBH17 95 CB17/CBH17−95
HS29−120 HS29−120 CB17/CBH17−135 CB17/CBH17−135
* If line length is greater than 25 feet (8 m), add this amount. If line length is less than 25 feet (8 m), subtract this amount.
NOTE − Refrigerant line sets should not be longer than 100 feet (30 m). Refrigerant line losses deduct from the net capacity
of the system. The additional refrigerant required for such systems may also upset the refrigerant to oil ratio.
Outdoor Coil HS29−072*
Entering Air Discharge
Temperature + 10 psig
65_F (18_C) 173
75_F (24_C) 199
85_F (29_C) 229
95_F (35_C) 261
105_F (40_C) 298
115_F (46_C) 333
*HS29−072 tested with CB30U−65. Pressure shown is with typical 5 ton indoor coil match up.
**HS29−072 and HS29−090 tested with CB17/CBH17−95V.
***HS29−120 tested with CB17/CBH17−135V.
Units are shipped with a holding charge of dry air and
helium which must be removed before the unit is evac
uated and charged with refrigerant. In new installations,
the best and most accurate method of charging is to weigh
the refrigerant into the unit as indicated in table 4. Add the
weight of the refrigerant or an approximate amount into the
unit. If weighing facilities are not available, or if the charge
needs to be checked, use the following method:
1 − Attach the gauge manifolds and operate the unit in
cooling mode until the system stabilizes (approximate
ly five minutes).
2 − Use a digital thermometer to accurately measure the
outdoor ambient temperature.
MATCHED HCFC 22 FOR 25 FEET
(7.62 M) OF LINE
12 lbs 8 oz (5 7 Kg) 12 lbs. 8 oz. (5.7 Kg)
17 5 lbs (7 9 Kg) 17.5 lbs. (7.9 Kg)
23 lbs. (10.4 Kg) 23 lbs (10 4 Kg)
Normal Operating Pressures
HS29−072* HS29−072**
Suction Discharge
+ 5 psig + 10 psig
61 180
63 207
65 238
67 271
71 308
72 342
Table 4
LIQUID LINE
DIAMETER
1/2 in. (13 mm)
5/8 in. (16 mm)
5/8 in. (16 mm)
3/4 in. (19 mm)
5/8 in. (16 mm)
3/4 in. (19 mm)
Table 5
HS29−072** HS29−090**
Suction Discharge
+ 5 psig + 10 psig
73 189
75 217
77 245
79 278
82 314
83 352
3 − Apply the outdoor temperature to table 5 to determine
normal operating pressures.
4 − Compare the normal operating pressures in table 5 to
the pressures obtained from the gauges. Minor varia
tions in these pressures may be expected due to differ
ences in installations. Significant differences could
mean that the system is not properly charged or that a
problem exists with some component in the system.
Correct any system problems before proceeding.
5 − Add or remove the charge in increments and allow the
system to stabilize each time you add or remove the
refrigerant.
6 − Use the approach method to confirm readings.
Page 21
ADJUSTMENT PER
FOOT (.305 M) OF
LINE*
1.1 oz. (31 g)
1.8 oz. (51 g)
1.8 oz. (51 g)
2.6 oz. (74 g)
1.8 oz. (51 g)
2.6 oz. (74 g)
HS29−090** HS29−120***
Suction Discharge
+ 5 psig + 10 psig
72 169
73 197
75 226
76 256
77 290
79 328
HS29−120***
Suction
+ 5 psig
63
67
70
71
73
74