Hot Gas Valve - Hoshizaki KMD-210AB-HC Service Manual

5. HOT GAS VALVE

To ensure optimum performance, use a copper tube of the same diameter and
length for replacement of the hot gas circuit.
Always install a new drier every time the sealed refrigeration system is opened.
Do not replace the drier until after all other repair or replacement has been made.
1) Turn off the power supply.
2) Remove the panels.
3) Remove the refrigerant from the unit and then any residual refrigerant still existing in the
unit to allow welding process. (See "2. WELDING REPAIR FOR R290 REFRIGERATION
CIRCUIT".)
4) Disconnect the hot gas valve leads.
5) Remove the screw and the solenoid coil.
6) Remove the valve and drier using brazing equipment.
7) Braze the new hot gas valve with nitrogen gas flowing at a pressure of 20 to 30 kPa.
Always protect the valve body by using a damp cloth to prevent the valve from
overheating. Do not braze with the valve body exceeding 135°C.
8) Install the new drier (see "V. 4. DRIER").
9) Check for leaks using nitrogen gas (970 kPa) and soap bubbles.
10) Evacuate the system and charge it with refrigerant (see "V. 1. [d] EVACUATION AND
RECHARGE").
11) Attach the solenoid coil to the valve body, and secure it with the screw.
12) Connect the lead wires.
13) Refit the panels in their correct positions.
14) Turn on the power supply.
CAUTION
IMPORTANT
WARNING
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