Panasonic CU-E18CKR Service Manual page 67

be thoroughly cleaned, but this is difficult with the present
technology.
10.4.4. Refrigerant Compatibility (Using R410A Refrigerant in R22 ACs and Vice
Versa)
Do not operate an existing R22 AC with the new R410A refrigerant. Doing so would result in
improper functioning of the equipment or malfunction, and might lead to a major accident such
as an explosion in the refrigeration cycle. Similarly, do notoperate an R410A AC with R22
refrigerant. The chemical reaction between the refrigerating machine oil used in R410A ACs and
the chlorine that is contained in R22 would cause the refrigerating machine oil to degrade and
lead to malfunction.
10.4.5. Recharging Refrigerant During Servicing
When recharging is necessary, insert the specified amount of new refrigerant in accordance
with the following procedure.
1. Connect the charging hose to the service port of the outdoor unit.
2. Connect the charging hose to the vacuum pump adaptor. At this
time, fully open the 2-way valve and 3-way valve.
3. Fully open the handle Lo of the manifold gauge, turn on the power
of the vacuum pump and continue the vacuum process for at
least one hour.
4. Confirm that the low pressure gauge shows a reading of -0.1 Mpa
(-76 cmHg), then fully close the handle Lo, and turn off the
vacuum pump. Wait for 1-2 minutes, then check to make sure that
the needle of the Low pressure gauge has not returned. SeeFig.
13 for the remaining steps of this procedure.
5. Set the refrigerant cylinder onto the electronic scale, then correct
the hose the cylinder and to the connection port for the electronic
scale. (1)(2)
Precaution:
Be sure to set up the cylinder for liquid charging. If you use a
cylinder equipped with a siphon tube, you can charge the liquid
without having to turn the cylinder around
6. Remove the charging hose of the manifold gauge from the
vacuum pump adaptor, and connect it to the connection port of
the electronic scale. (2)(3)
7. Open the valve of the refrigerant cylinder, then open the charging
valve slightly and close it. Next, press the check valve of the