Page 10
2 - RFCII Systems
The following procedures are intended as a general guide
for use with RFCII systems only. For best results, indoor
temperature should be between 70
°
F and 80
°
F. Outdoor
temperature should be 60
°
F or above. Slight variations in
charging temperature and pressure should be expected.
Large variations may indicate a need for further servicing.
IMPORTANT
The following procedure requires accurate readĆ
ings of ambient (outdoor) temperature, liquid temĆ
perature and liquid pressure for proper charging.
Use a thermometer with accuracy of +2
°
F and a
pressure gauge with accuracy of +5 PSIG.
1 - Connect gauge manifold. Connect an upright R-22
drum to center port of gauge manifold.
2 - Operate indoor and outdoor units. Allow outdoor unit
to run until system pressures stabilize.
3 - Make sure thermometer well is filled with mineral oil
before checking liquid line temperature.
4 - Place thermometer in well and read liquid line temĆ
perature.
5 - Read liquid line pressure.
6 - Convert liquid line pressure to condensing temperĆ
ature.
7 - Subtract liquid line temperature from condensing
temperature to determine subcooling. Compare
with table12.
8 - Add refrigerant to increase subcooling. Remove
refrigerant to decrease subcooling.
9 - When unit is properly charged liquid line
pressures should approximate those given in
table 11.
TABLE 12
Outdoor
Temp. (
_
F)
Liquid Subcooling (+ 1
°
F)
SUBCOOLING METHOD
Ć141
Ć211 Ć261 Ć311 Ć410 Ć460 Ć510 Ć650
60
65
70
75
80
85
90
95
100
105
110
115
9
8
7
7
6
6
5
4
4
3
3
2
11
11
10
10
9
9
8
8
7
6
6
5
14
14
13
13
12
12
11
11
10
10
9
8
18
17
17
16
16
15
15
14
13
12
11
9
15
14
13
12
11
10
9
8
6
5
4
2
15
15
14
14
13
13
12
12
11
10
10
9
20
19
19
18
18
17
17
16
15
15
14
13
17
16
16
15
15
14
14
13
13
12
11
10
D - Oil Charge
Table 4 on page 3 shows the factory oil charge in HS24 units.
V - Maintenance
At the beginning of each heating or cooling season, the
system should be cleaned as follows:
A - Outdoor Unit
1 - Clean and inspect condenser coil. (Coil may be
flushed with a water hose).
2 - Condenser fan motor is prelubricated and ports are
sealed with plugs. No further lubrication is required.
Oiling ports can be accessed for lubrication after exĆ
tended operation by removing plugs. Be sure to seĆ
curely seal after servicing.
3 - Visually inspect all connecting lines, joints and coils
for evidence of oil leaks.
IMPORTANT
If insufficient heating or cooling occurs, the unit
should be gauged and refrigerant charge
checked.
B - Indoor Coil
1 - Clean coil if necessary.
2 - Check connecting lines, joints and coil for evidence
of oil leaks.
3 - Check condensate line and clean if necessary.
C - Indoor Unit
1 - Clean or change filters.
2 - Use the following as a guide when lubricating
the blower motor:
a-
Motors without Oiling Ports --
Prelubricated
and sealed. No further lubrication required.
b-
Direct Drive Motors with Oiling Ports --
PreluĆ
bricated for an extended period of operation.
For extended bearing life, relubricate with a
few drops of SAE 10 non-detergent oil once
every two years. It may be necessary to reĆ
move blower assembly for access to oiling
ports.
3 - Adjust blower speed for cooling. The static presĆ
sure drop over the coil should be checked to deterĆ
mine the correct blower CFM. Refer to Lennox EnĆ
gineering Handbook for Static Pressure and CFM
tables.
4 - Check all wiring for loose connections.
5 - Check for correct voltage at unit.
6 - Check amp-draw on blower motor.
Unit nameplate_________Actual_________.
