Panasonic CS-PV9DKE, Руководство по обслуживанию

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<Brazing Method for Preventing Oxidation>
1. Attach a reducing valve to the nitrogen gas cylinder.
2. Attach a reducing valve to the nitrogen gas cylinder.
3. Apply a seal onto the clearance between the piping and inserted pipe for the nitrogen gas in order to prevent the nitrogen gas
from flowing backward.
4. When the nitrogen gas is flowing, be sure to keep the piping end open.
5. Adjust the flow rate of nitrogen gas so that it is lower than 0.05 m
3
/h, or 0.02 MPa (0.2 kgf/cm
2
) by means of the reducing valve.
6. After taking the steps above, keep the nitrogen gas flowing until the piping cools down to a certain extent (i.e. temperature at
which pipes are touchable with finger).
7. Completely remove the flux after bra z ing.
Cautions during brazing
1. General Cautions
a. The bra z ing strength should be high as required.
b. After operation, airtightness should be kept under pressuri z ed condition.
c. During bra z ing do not allow component materials to become damaged due to overheating.
d. The refrigerant pipe work should not become blocked with scale or flux.
e. The bra z ed part should not restrict the flow in the refrigerant circuit.
f. No corrosion should occur from the bra z ed part.
2. Preventing of Overheating
Due to heating, the interior and exterior surfaces of treated metal may oxidi z e. Especially, when the interior of the refrigerant
circuit oxidi z es due to overheating, scale occurs and stays in the circuit as dust, thus exerting a fatally adverse effect. So,
make bra z ing at adequate bra z ing temperature and with minimum of heating area.
3. Overheating Protection
In order to prevent components near the bra z ed part from overheating damaged or quality deterioration due to flame or heat,
take adequate steps for protection such as (1) by shielding with a metal plate, (2) by using a wet cloth, and (3) by means
of heat absorbent.
4. Movement during Bra z ing
Eliminate all vibration during bra z ing to protect bra z ed joints from cracking and breakage.
5. Oxidation Preventative
In order to improve the bra z ing efficiency, various types of antioxidant are available on the market. However, the
constituents of these are widely varied, and some are anticipated to corrode the piping materials, or adversely affect HFC
refrigerant, lubricating oil, etc. Exercise care when using an oxidation preventive.
10.4.7. Servicing Tips
The drier must also be replaced whenever replacing the refrige rant cycle parts. Replacing the refrigerant cycle parts first
before replacing the drier. The drier is supplie d in a vacuum pack. Perform bra
z ing immediately after openin g the vacuum
pack, and then start the vacuum within two hours. In addition, the drier also needs to be replace d when the refrigerant has
leaked completely.
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CS-PV9DKE / CU-PV 9DKE / CS-PV12DKE / CU-PV12DKE