Flushing The System - Lennox Merit Series 13ACX Installation Instructions Manual

(Uncased Coil Shown)
TWO PIECE
LIQUID LINE
PATCH PLATE
(UNCASED COIL ORIFICE
ONLY)
HOUSING
DISTRIBUTOR
EQUALIZER
ASSEMBLY
LINE
MALE EQUALIZER
SENSING
LINE FITTING
BULB
SUCTION
Figure 17. Typical TXV Removal
8. Use a field−provided fitting to temporary reconnect the
liquid line to the liquid line orifice housing.

Flushing the System

IMPORTANT
The line set and indoor unit coil must be flushed
with at least the same amount of clean refrigerant
that previously charged the system. Check the
charge in the flushing cylinder before proceeding.
IMPORTANT
If this unit is being matched with an approved line
set or indoor unit coil which 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 insulator,
preventing proper heat transfer. It can also clog
the expansion device, and reduce the system
performance and capacity.
Failure to properly flush the system per the
instructions below will void the warranty.
IMPORTANT
The Environmental
prohibits the intentional venting of HFC refrigerants
during maintenance, service, repair and disposal of
appliance. Approved
recycling or reclaiming must be followed.
506081−01 09/08
STUB END
TXV
TEFLON
RING
TEFLON
SENSING
RING
LINE
LIQUID LINE ASSEMBLY
WITH BRASS NUT
LIQUID
LINE
LINE
Protection Agency
methods of recovery,
If the original system used:
S
HCFC−22 refrigerant, then flush the system using the
procedure provided in this section.
S
HFC−410A refrigerant, then proceed to Installing New
Refrigerant Metering Device.
SUCTION LINE
SERVICE VALVE
EXISTING
INDOOR
UNIT
LIQUID LINE SERVICE VALVE
RECOVERY
CYLINDER
NOTE − The inverted HCFC−22 cylinder must contain at least the same
amount of refrigerant as was recovered from the existing system.
Figure 18. Typical Flushing Connection
This procedure should not be performed on
systems which contain contaminants (Example:
compressor burn out).
REQUIRED EQUIPMENT
Equipment required to flush the existing line set and indoor
unit coil:
S
Two clean HCFC−22 recovery bottles,
S
Oilless recovery machine with pump-down feature,
S
Two gauge sets (one for HCFC−22; one for
HFC−410A).
FLUSHING PROCEDURE
1. Connect the following:
S
HCFC−22 cylinder with clean refrigerant to the
suction service valve,
S
HCFC−22 gauge set to the liquid line valve,
S
Recovery machine with an empty recovery tank to
the gauge set.
2. Set the recovery machine for liquid recovery and start
the recovery machine. Open the gauge set valves to
allow the recovery machine to pull a vacuum on the
existing system line set and indoor unit coil.
3. Invert the cylinder of clean and open its valve to allow
liquid refrigerant to flow into the system through the
suction line valve. Allow the refrigerant to pass from
the cylinder and through the line set and the indoor unit
(EPA)
coil before it enters the recovery machine.
4. After all of the liquid refrigerant has been recovered,
switch the recovery machine to suction recovery so
that all of the suction is recovered. Allow the recovery
machine to pull a vacuum on the system.
Page 10
INVERTED HCFC−22 CYLINDER
CONTAINS CLEAN HCFC−22 TO
BE USED FOR FLUSHING.
LOW
PRESSURE
NEW
OUTDOOR
UNIT
OPENED
TANK
RETURN
INLET
DISCHARGE
RECOVERY MACHINE
CAUTION
GAUGE
MANIFOLD
HIGH
PRESSURE
CLOSED