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minimum opening in hot water or heating mode is L22 ~ L26. The adjustment interval time is L04 seconds. The
electronic expansion valve of each system works and adjusts independently;
Hot water / heating mode:
△
P = suction temperature
–
coil temperature
–
L22 ~ L26
Cooling mode:
△
P = suction temperature - temperature after refrigeration valve -L05
In hot water or heating mode, when the ambient temperature is not less than L14 and the water temperature is not
less than L15,
△
P = suction temperature - coil temperature - L13;
Restrictions on opening of main circuit electronic expansion valve:
①
when the suction temperature is higher than L12, the value of the electronic valve increases gradually with 8
pulses, and it can reach the maximum value; when the suction temperature is lower than L12-2
℃
, it enters
normal regulation;
②
when the discharge gas temperature of the compressor is
≥
L10, the value of the electronic valve increases
gradually with 8 pulses, and it can reach the maximum value; when the discharge gas temperature of the
compressor is
≤
L10
℃
, it exits this regulation;
③
when the discharge gas temperature is higher than L11, the value of the electronic valve increases gradually
with 8 pulses, and it can reach the maximum value; when the discharge gas temperature is lower than L11-2
℃
, it
enters normal regulation;
Note: the superheat and the minimum opening of the electronic expansion valve of the main circuit are divided
into 5 areas according to the table below.
5.2 auxiliary electronic expansion valve
1) after the enthalpy increasing valve closes, the electronic expansion valve of the auxiliary circuit will fully close;
2) after the enthalpy increasing valve opens, the auxiliary electronic expansion valve will open to the initial opening
set in parameter L16. After the compressor starts for 2 minutes, If inlet water temperature and discharge gas
temperature are detected, the opening of the EEV will be adjusted according to the following rules. The maximum
opening is 60 and the minimum opening is L17. The adjustment interval time is L4 seconds;
△
P = discharge gas temperature
– inlet water temperature - 35
℃
- L18;
When |
△
p| = 2, the electronic expansion valve of the auxiliary circuit maintains the current opening.
6. Logic of defrost control
This function is only valid in hot water mode or heating mode;
6.1 conditions for defrosting
1) when the ambient temperature is
≥
H08 (default - 6
℃
) + 1
℃
, coil temperature is
≤
H02 (default -
-17 -15 -10 -8 -4 -2 3 5 Ambient (
℃
)
A ZONE
B ZONE
C ZONE
D ZONE
E ZONE