Panasonic WH-SDF16C9E8 [62/125] Protection control for heating operation

13.1.6 Low Frequency Protection Control 1

 When the compressor continuously operates at frequency lower than 25 Hz for 240 minutes, the operation

frequency will change to 24 Hz for 2 minutes.

13.1.7 Low Frequency Protection Control 2

 When all the below conditions comply, the compressor frequency will change to lower frequency.

Temperature, T, for: Heating

Outlet water (°C) T < 14 or T 48

Outdoor air (°C) T < 4 or T 24

Indoor heat exchanger (°C) T 0

13.1.8 High Pressure Sensor Control

 Purpose:

- To protect the system operation.

 Detection period:

- After compressor on for 5 minutes.

 Detection conditions:

- When abnormal high voltage detection, 5V or when open circuit detection 0V for 5 seconds continuously.

 After detection:

- When abnormality is detected continue 5 seconds, unit stop operation.

- OFF/ON control panel LED will blink (H64 error occurs).

13.1.9 Outside Temperature Current Control

13.1.10 Crank Case Heater Control

 Purpose:

- For compressor protection during low outdoor ambient operation (during heating low temperature operation).

 Control content:

a. Trigger heater START condition

o When the outdoor air temperature is 4°C or below, and discharge temperature is 11.6°C or below.

b. Resetting heater STOP condition

1. When the outdoor air temperature exceeds entry condition (6°C)

2. When the discharge temperature exceeds entry condition (18.8°C)

13.2 Protection Control for Heating Operation

13.2.1 Outdoor Air Temperature Control

The maximum current value is regulated when the outdoor air temperature rises above 14°C in order to avoid

compressor overloading.

13.2.2 Deice Operation

When outdoor pipe temperature and outdoor air temperature is low, deice operation start where outdoor fan motor

stop.