Hoshizaki RF28A, Руководство по обслуживанию

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B. Brazing
DANGER
1. Refrigerants R-404A and R-134a are not flammable at atmospheric pressure
and ambient temperature.
2. Refrigerants R-404A and R-134a themselves are not explosive or poisonous.
However, when exposed to high temperatures (open flames) these
refrigerants can be decomposed to form hydrofluoric acid and carbonyl
fluoride, both of which are hazardous.
3. Always recover the refrigerant and store it in an approved container. Do not
discharge the refrigerant into the atmosphere.
4. Do not use silver alloy or copper alloy containing arsenic.
5. Do not use R-404A or R-134a as a mixture with pressurized air for leak
testing. Refrigerant leaks can be detected by charging the unit with a little
refrigerant, raising the pressure with nitrogen and using an electronic leak
detector.
C. Removal and Replacement of Compressor
Note: When replacing a compressor with a defective winding, be sure to install the start
capacitor, overload and start relay.
1) Turn off the power supply, and unplug the unit.
2) Remove the panels.
3) Recover the refrigerant and store it in an approved container.
4) Remove the terminal cover on the compressor and disconnect the compressor wiring.
(Be sure to discharge the start capacitor.)
5) Remove the discharge, process and suction pipes from the old compressor.
6) Remove the hold-down bolts, washers, rubber grommets and sleeves.
7) Remove the old compressor.
8) Unpack the new compressor package. Attach the rubber grommets and sleeves of the
prior compressor if the new compressor is not supplied with them.
9) Place the compressor in position, and secure it using the bolts and washers.
10) Remove the drier, then place the new drier in position.
11) Remove the plugs from the suction, discharge and process pipes.
12) Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 psig.
13) Check for leaks using nitrogen gas (140 psig) and soap bubbles.
14) Evacuate the system, and charge it with refrigerant; see the nameplate for the
required refrigerant charge.
15) Connect the terminals, then replace the terminal cover in its correct position.
16) Replace the panels in their correct positions.
17) Plug in the unit, and turn on the power supply.