DOWNLOAD Panasonic WH-MXC16G9E8 Service Manual ↓ Size: 10.68 MB | Pages: 127 in PDF or view online for FREE

77 

1  The compressor will not start for three minutes after stop of operation. 

1  Once the compressor starts operation, it will not stop its operation for 30 seconds. 
2  However, it can be stopped using control panel at indoor unit. 

1  When the outdoor running current exceeds X value, the compressor frequency will decrease. 
2  If the outdoor running current does not exceed X value, the compressor frequency will return to normal 

operating frequency. 

3  If the outdoor running current continue to increase till exceed Y value, compressor will stop, and if this occurs 

3 times within 20 minutes, system will stop operation and OFF/ON control panel LED will blink (F16 error 
occurs). 

 

 

MXC16G9E8 

Operation Mode 

X (A) 

Y (A) 

Heating 

15.5 

16.5 

Cooling 

7.1 

16.5 

 

A.  DC Peak Current Control 

1  When the current to IPM exceeds set value of 54.0 A +/- 4.0 A, compressor will stop. Compressor will restart 

after three minutes. 

2  If the set value exceeds again for more than 30 seconds after the compressor restarts, operation will restart 

after two minutes.  

3  If the set value exceeds again for within 30 seconds after the compressor restarts, operation will restart after 

one minute. If this condition repeats continuously for seven times, system will stop operation and OFF/ON 
control panel LED will blink (F23 error occurs). 

  The compressor operating frequency is regulated in accordance to compressor tank temperature as shown in 

below figures. When the compressor tank temperature exceeds 107°C, compressor will stop, and if this occurs 4 
times within 30 minutes, system will stop operation and OFF/ON control panel LED will blink (F20 error occurs). 

 

Compressor = OFF

Free

105°C

99°C

Compressor tank temperature

101°C

107°C

101°C

99°C

Compressor

Frequency Reduced

Compressor

Frequency Maintain

 

 

  When the compressor continuously operates at frequency lower than 21 Hz for 240 minutes, the operation 

frequency will change to 20 Hz for 2 minutes. 

 

78 

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

Temperature, T, for: 

Heating 

Cooling 

Outlet water (°C) 

T < 14 or T ≥ 48 

T < 14 or T ≥ 30 

Outdoor air (°C) 

T < 4 or T ≥ 24 

T < 13 or T ≥ 38 

Indoor heat exchanger (°C) 

T ≥ 0 

T < 30 

  Purpose: 

- To protect the system operation. 

  Detection period: 

- After compressor on for 1 minute. 

  Detection conditions: 

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

  After detection: 

- When abnormality is detected 4 times within 120 minutes, unit stop operation. 
- OFF/ON control panel LED will blink (H64 error occurs). 

 

23°C

21°C

14°C

12°C

-25°C

-28°C

Compressor stop

Outdoor temperature

Max.

current

value is

regulated

 

  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 below than 5°C, and discharge temperature is 11°C or below. 

b.  Resetting heater STOP condition 

1. 

When the outdoor air temperature exceeds entry condition (2°C) 

2. 

When the discharge temperature exceeds entry condition (5°C) 

 
 
 
 
 
 
 
 
 
 
 
 
 
 

79 

 

Water Inlet

10°C

12°

Free Zone

(Compressor ON,

Heater OFF)

Deice (Compressor OFF,

Heater ON)

 

 

  Start Condition: 

- When outdoor ambient temperature is less than 10°C. 
 

  Control Details: 

- Heater will turn ON and heat pump turn OFF when water inlet temperature below 10°C. 
- Heater will turn OFF and heat pump turn ON when water inlet temperature increase more than 12°C. 

 

  End Condition: 

- When outdoor ambient temperature is more than 13°C. 
 

However this control will take place 29 minutes after compressor restart. 

80 

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

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

  Deice judging condition 

 

-30

-30

-20

-10

0

10

20

30

-25

-20

-15

-10

-5

0

5

10

O

D

 P

ip

e 

T

e

m

p

e

rat

u

re 

(°

C)

Outdoor Unit Deice Control

line for continuous 3 minutes

and Pipe Temperature below this

When Heating Time > 35 minutes

Outdoor Temperature (°C)

3. Heating accumulation time

1. Outdoor air sensor temp.

2. Outdoor pipe sensor temp.

 

 

  Deice mode selection condition 

o

  There are 2 deice modes, according to water inlet temperature and outdoor ambient temperature the deice 

mode is decided. 

 

50°C

27°C

-

10°C

Water inlet temperature

Outdoor ambient temperature

Deice mode 1

Deice mode 2

 

 

Judgement details: 

1)  When water inlet temperature is more than 50°C, unit will operate deice mode 1. 
2)  When water inlet temperature is less than 27°C, unit will operate deice mode 2. 
3)  When water inlet temperature is less than 50°C and outdoor ambient temperature is less than -10°C, unit will 

operate deice mode 2. 

4)  When water outlet temperature sensor 2 detect temperature is less than 22°C, unit will operate deice mode 2.