Air Purging - Sanyo SAP-KRV9AEH Installation Instructions Manual

4-3. Air Purging

Air and moisture remaining in the refrigerant system
have undesirable effects as indicated below. There-
fore, they must be purged completely.
• Pressure in the system rises
• Operating current rises
• Cooling (or heating) efficiency drops
• Moisture in the air may freeze and block capillary
tubing
• Water may lead to corrosion of parts in the refriger-
ant system
Air Purging With a Vacuum Pump (for Test Run)
(1) Check that each tube (both narrow and wide
tubes) between the indoor and outdoor units have
been properly connected and all wiring for the test
run has been completed. Note that both narrow
and wide tube service valves on the outdoor unit
are kept closed at this stage.
(2) Using an adjustable wrench or box wrench,
remove the valve caps from the service on both the
narrow and wide tubes.
(3) Connect a vacuum pump and a manifold valve
(with pressure gauges) to the service port on the
wide tube service valve. (Fig. 35)
G
CAUTION
G
(4) With the "Lo" knob of the manifold valve open, run
the vacuum pump. The operation time for the vacu-
um pump varies with tubing length and the capaci-
ty of the pump. The following table shows the
amount of time for evacuation:
Table 3
Required time for evacuation when
capacity of 100 liter/h vacuum pump is used
If tubing length is
less than 10 m
10 min. or more
The service port on the wide
tube service valve uses a
Schrader core valve to access
the refrigerant system. The
valve core is similar to those
used in automobile tires.
Therefore, be sure to use a vac-
uum hose connector which has
a push-pin inside.
Be sure to use a manifold valve
for air purging. If it is not avail-
able, use a stop valve for this
purpose. The "Hi" knob of the
manifold valve must always be
kept closed.
If tubing length is
The required time in Table 3 is calculated based on the
more than 10 m
assumption that the ideal (or target) vacuum condition is
15 min. or more
around 10 mmHg abs.
Manifold valve
(Exclusively for R410A)
Pressure
gauge
Vacuum pump
NOTE
• To prevent other refrigerants from being mis-
takenly charged to units which use R410A,
the size of the charge port on the service
valve is different from the one for other
refrigerant types. For servicing such as
recharging, the specified charging hose,
manifold, and vacuum pump adapter (with
reverse flow prevention) for R410A must be
used.
NOTE
13
Indoor unit
Outdoor unit
Lo Hi
Charging hose
(Exclusively for R410A)
Vacuum pump adapter
(Exclusively for R410A)
(with reverse flow
prevention)
Fig. 35