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V−SERVICE AND RECOVERY
WARNING
Polyol ester (POE) oils used with R410A 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 ser-
vice valve stub caps until you are ready to make
connections.
IMPORTANT
Use recovery machine rated for R410 refrigerant.
If the HPXA19 system must be opened for any kind of ser-
vice, such as compressor or filter drier replacement, you
must take extra precautions to prevent moisture from en-
tering the system. The following steps will help to minimize
the amount of moisture that enters the system during re-
covery of R410A.
1 − Use a regulator−equipped nitrogen cylinder to break
the system vacuum. Do not exceed 5 psi. The dry ni-
trogen will fill the system, and will help purge any mois-
ture.
2 − Remove the faulty component and quickly seal the
system (using tape or some other means) to prevent
additional moisture from entering the system.
3 − Do not remove the tape until you are ready to install
new component. Quickly install the replacement com-
ponent.
4 − Evacuate the system to remove any moisture and oth-
er non−condensables.
The HPXA19 system MUST be checked for moisture
any time the sealed system is opened.
Any moisture not absorbed by the polyol ester oil can be re-
moved by triple evacuation. Moisture that has been ab-
sorbed by the compressor oil can be removed by replacing
the filter drier.
IMPORTANT
Evacuation of system only will not remove mois-
ture from oil. Filter drier must be replaced to elimi-
nate moisture from POE oil.
VI−MAINTENANCE
WARNING
Electric shock hazard. Can cause inju-
ry or death. Before attempting to per-
form any service or maintenance, turn
the electrical power to unit OFF at dis-
connect switch(es). Unit may have
multiple power supplies.
Maintenance and service must be performed by a quali-
fied installer or service agency. At the beginning of each
cooling or heating season, the system should be checked
as follows:
Outdoor Unit
1 − Clean and inspect outdoor coil (may be flushed with a
water hose). Ensure power is off before cleaning.
2 − Outdoor unit fan motor is prelubricated and sealed. No
further lubrication is needed.
3 − Visually inspect all connecting lines, joints and coils for
evidence of oil leaks.
4 − Check all wiring for loose connections.
5 − Check for correct voltage at unit (unit operating).
6 − Check amp−draw on outdoor fan motor and compres-
sor (high and low capacity).
7 − Inspect drain holes in coil compartment base and
clean if necessary.
NOTE − If owner complains of insufficient cooling, the unit
should be gauged and refrigerant charge checked. Refer to
section on refrigerant charging in this instruction.
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.
Indoor Unit
1 − Clean or change filters.
2 - Lennox blower motors are prelubricated and permanent-
ly sealed. No more lubrication is needed.
3 − Adjust blower speed for cooling. Measure the pressure
drop over the coil to determine the correct blower CFM.
Refer to the unit information service manual for pressure
drop tables and procedure.
4 −
Belt Drive Blowers −
Check belt for wear and proper
tension.
5 − Check all wiring for loose connections.
6 − Check for correct voltage at unit.
7 − Check amp−draw on blower motor.
