Hoshizaki KM-1301SAH-E, KM-1301SRH-E, KM-1301SWH-E Brazing, Evacuation and Recharge R-404A

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2. Brazing

WARNING

1.R-404A itself is not flammable at atmospheric pressure and temperatures up to 176°F (80°C).

2.R-404A itself is not explosive or poisonous. However, when exposed to high temperatures (open flames), R-404A can be decomposed to form hydrofluoric acid and carbonyl fluoride both of which are hazardous.

3.Do not use silver alloy or copper alloy containing arsenic.

4.Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). DO NOT use R-404A as a mixture with pressurized air for leak testing.

1)Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG. Note: Because the pipes in the evaporator case are specially coated to resist corrosion,

it is important to make connections outside the evaporator case when possible. If it is necessary to braze inside the evaporator case, use sandpaper to remove the coating from the brazing connections before unbrazing the components.

CAUTION

1.Always install a new drier every time the sealed refrigeration system is opened.

2.Do not replace the drier until after all other repair or replacement has been made. Install the new drier with the arrow on the drier in the direction of the refrigerant flow.

3.When brazing, protect the drier by using a wet cloth to prevent the drier from overheating. Do not allow the drier to exceed 250°F (121°C).

2)Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). DO NOT use R-404A as a mixture with pressurized air for leak testing.

3.Evacuation and Recharge (R-404A)

1)Attach a vacuum pump to the system. Be sure to connect the charging hoses to both high and low-side service valves.

IMPORTANT

The vacuum level and vacuum pump may be the same as those for current refrigerants. However, the rubber hose and gauge manifold to be used for evacuation and refrigerant charge should be exclusively for POE oils.

2)Turn on the vacuum pump. Open the gauge manifold valves, then open the high and low-side service valves. Never allow the oil in the vacuum pump to flow backwards.

3)Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends on pump capacity.

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Contents Superior Degree Reliability Hoshizaki AMERICA, INC Contents Page Important Safety Information Serious injuryIndicates important information about the use and care UnitSpecifications Icemaker KM-1301SAH-E air-cooledKM-1301SWH-E water-cooled KM-1301SRH-E remote air-cooled Condenser Unit URC-14FESpecifications II. General Information Construction KM-1301SWH-E water-cooled Separators Sequence of Operation Sequence Cycles and ShutdownMinute Fill Cycle Initial Harvest CycleS4 Dip Switch Setting Pump-Out 1st Pump-Out Frequency Freeze CyclePump-Out Cycle Harvest CycleMechanical Bin Control KM-1301SWH-E, KM-1301SRH-E Cycle at Shutdown Mechanical Bin Control ActivationSequence Flow Chart Cycle Steps Minute Fill Harvest CyclePump-Out Cycle Mechanical BC Bin Full Shutdown and RestartControl Board Control Board Layout Control BoardLED Lights and Audible Alarm Safeties No. of Beeps Type of Alarm Every 3 secSequence Step Time LEDs are OnDefault Dip Switch Settings Controls and AdjustmentsHarvest Timer S4 dip switch 1 Pump-Out Frequency Control S4 dip switch 5 Pump-Out Timer S4 dip switch 3Time seconds Inlet Harvest Pump Timer S4 dip switch Factory Use S4 dip switchFreeze Timer S4 dip switch 9 S4 Dip Switch Setting Pump Motor Time secondsFloat Switch Control S5 dip switch Control SwitchRefill Counter S5 dip switch 2 through Tank Water Tank Headmaster Service Drier Valve Thermistor Wiring Diagrams Auxiliary Code T-0, U-0KM-1301SAH-E air-cooled U-0 Auxiliary CodeAuxiliary Code U-1 and Later PressureSwitch KM-1301SRH-E remote air-cooled Performance Data 1330 12401780 13351270 11421950 2070IV. Service Diagnosis Diagnostic ProcedurePage S4 Dip Switch Setting Pump-Out 1st Pump-Out Frequency Shutdown Thermostatic Bin Control KM-1301SAH-E Mechanical Bin Control KM-1301SWH-E, KM-1301SRH-EControl Board Check Thermostatic Bin Control Check KM-1301SAH-E Bin Control CheckMechanical Bin Control Check Single Unit Connection Detail Stacked Unit Connection DetailMechanical Bin Control Cleaning Float Switch Check and Cleaning Float Switch CheckFloat Switch Cleaning Adjustment of Water Regulating Valve water-cooled model Thermistor CheckNo Ice Production Diagnostic ChartsNo Ice Production Possible Cause No Ice Production Possible Cause Freeze Up Freeze Up Possible Cause Harvest CycleFreeze Up Possible Cause Freeze Cycle Low Ice Production Possible Cause Long Harvest Cycle Low Ice ProductionLong Freeze Cycle Service for Refrigerant Lines Replacement of ComponentsRefrigerant Recovery Brazing Evacuation and Recharge R-404APage Important Notes for Component Replacement ComponentVI. Cleaning and Maintenance Cleaning ProcedureIce Chute Float Switch Assembly Drain Plug Sanitizing Procedure Following Cleaning Procedure Maintenance Remove the water from the icemaker water supply lineDrain the water tank
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