Hoshizaki FTC-120MDA, Service Manual

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21
[f] COMPRESSOR SOFT START
1) Startup
When the power supply is turned on, the screen shows the cabinet temperature and the
interior fan motor starts up immediately (RTC series only) or with a 1 minute delay (FTC
series). The compressor and condenser fan motor start up with a 3 minute delay.
This delay is intended to minimize the difference between the high-side and low-side
pressures and to reduce the load on the compressor so that it can start easily in case of a
short (especially instantaneous) power failure.
2) Normal Control
Power ON
3 min
Compressor
Condenser Fan Motor
Cabinet Temp Display
Interior Fan Motor (RTC)
ON
OFF
ON
OFF
1 min
Interior Fan Motor (FTC)
ON
OFF
3 min 3 min
Compressor
Condenser Fan Motor
Interior Thermistor
Set Point + 4K
ON
OFF
Set Point
When the compressor turns off during normal control, it has a mandatory 3 minute delay
before startup. For example, if the compressor turns off by its thermistor and the door is
opened immediately after (causing the cabinet temperature to immediately exceed the
restart temperature), the compressor will still not start until 3 minutes have passed since its
shutdown.
[g] HIGH PRESSURE SWITCH (FTC series only)
4.0 MPa
3.0 MPa
Pressure Switch
Compressor
Condenser Fan Motor
ON
OFF