Lennox Merit 13ACX-018-230 Installation Instructions Manual page 4

STEP 2 -- REFRIGERANT PIPING -- Flushing Existing Line Set and Indoor Coil
Flush the existing line set per the
instructions. For more information, refer to the
Installation and Service Procedures manual available
on DaveNet. CAUTION - DO NOT attempt to flush and
re-use existing line sets or indoor coil when the system
contains contaminants (i.e., compressor burn out).
NOTE - When installing refrigerant lines longer than 50 feet,
refer to the Refrigerant Piping Design and Fabrication
Guidelines manual available on DaveNet (Corp. 9351-L9),
or contact the Technical Support Department Product
Application group for assistance.
IMPORTANT !
If this unit is being matched with an approved line set
or indoor unit coil that was previously charged with
mineral oil, or if it is being matched with a coil which
was manufactured before January of 1999, the coil
and line set must be flushed prior to installation. Take
care to empty all existing traps. Polyol ester (POE)
oils are used in Lennox units charged with HFC-410A
refrigerant. Residual mineral oil can act as an insula­
tor, preventing proper heat transfer. It can also clog
the expansion device and reduce system perfor­
mance and capacity.
Failure to properly flush the system per this instruc­
tion and the detailed Installation and Service Proce­
dures manual will void the warranty.
WARNING
When using a high pressure gas such as
nitrogen to pressurize a refrigeration or air
conditioning system, use a regulator that
can control the pressure down to 1 or 2 psig
(6.9 to 13.8 kPa).
WARNING
Refrigerant can be harmful if it is inhaled. Refrigerant
must be used and recovered responsibly.
Failure to follow this warning may result in personal injury
or death.
Model Number (-xx*)
13ACX-018-230
13ACX-024-230
13ACX-030-230
13ACX-036-230
13ACX-042-230
13ACX-048-230
13ACX-060-230
* Applicable to all minor revision numbers unless otherwise specified.
** Some applications may required a field-provided 1-1/8" to 7/8" adapter.
following
REFRIGERANT LINE SET — INCHES (MM)
Valve Size Connections
Liquid Line Suction Line
3/8" (10 mm) 5/8" (16 mm)
3/8" (10 mm) 3/4" (19 mm)
3/8" (10 mm) 7/8" (22 mm)
Polyol ester (POE) oils used with HFC-410A
refrigerant absorb moisture very quickly. It is very
important that the refrigerant system be kept closed as
much as possible. DO NOT remove line set caps or
service valve stub caps until you are ready to make
connections.
Some scroll compressors have an internal vacuum
protector that will unload scrolls when suction pres­
sure goes below 20 psig. A hissing sound will be
heard when the compressor is running unloaded.
Protector will reset when low pressure in system is
raised above 40 psig. DO NOT REPLACE COMPRES­
SOR.
LIQUID LINE FILTER DRIER INSTALLATION
The filter drier (one is shipped with each 13ACX unit) must
be field installed in the liquid line between the outdoor unit's
liquid line service valve and the indoor coil's metering device
(fixed orifice or TXV) as illustrated in figure 6. This filter drier
must be installed to ensure a clean, moisture-free system.
Failure to install the filter drier will void the warranty. A
replacement filter drier is available from Lennox. See
Brazing Connections page 7 for special procedures on
brazing filter drier connections to the liquid line.
Typical Liquid Line Filter Drier Installation
LIQUID LINE
SERVICE VALVE
OUTDOOR
UNIT
TABLE 2
L15 Line Set Model
L15-26-20
L15-26-25
L15-26-35
L15-26-50
L15-41-20
L15-41-30
L15-41-40
L15-41-50
L15-65-30
L15-65-40
L15-65-50
Page 4
WARNING
IMPORTANT !
BRAZE CONNECTION POINTS
LINE
LIQUID LINE
FILTER DRIER
FIGURE 6
Recommended Line Sets
Line Set Length
20 feet (6.1 m)
25 feet (9.1 m)
35 feet (12.2 m)
50 feet (15.2 m)
20 feet (6.1 m)
30 feet (9.1 m)
40 feet (12.2 m)
50 feet (15.2 m)
30 feet (9.1 m)
40 feet (12.2 m)
50 feet (15.2 m)
LIQUID
LINE
Catalog Number
89J52
89J53
89J54
89J55
89J56
89J57
89J58
89J59
89J60
89J61
89J62