Daikin EUWY 24KBZW1 Series, Service Manual

Page: 106 / 210

Functional Description ESIE11-02
2–20 Part 2 – Functional Description
3
1
2
4
5
Starting defrost
function The table below describes the start conditions for the defrost function.
Terminating defrost
function The table below describes the terminating conditions for the defrost function.
Start condition 1
T
coil
C1/2 < 0.6 x T
amb
-10°C
AND
T
coil
C1/2 < -10°C
AND
T
amb
< 50°C
TimConditional
Depending on
dipswitch S2A-1
in combination
with EUWY
setting
(S1A-234)
Start condition 2
Start condition 2A:
T
coil
C1/2 < 0.6 x T
amb
-10°C
AND
T
coil
C1/2 < -10°C
AND
T
amb
< 50°C
TimConditional
OR
Start condition 2B:
T
coil
C1/2 < 0.6 x T
amb
-1°C
AND
T
coil
C1/2 < -1°C
AND
T
amb
< 50°C
TimConditional
AND
TimCompMin
Stop condition 1
{ (T
amb
at defrost start time
≥
B°C) AND (T
coil
C1/2 > +20°C) }
OR
{ (T
amb
at defrost start time < B°C) AND (T
coil
C1/2 > +10°C) }
B = 5°C
Stop condition 2
After Timdefrost Max:
The defrost operation can take maximum 10 minutes. After the 10
minutes defrost operation, the unit returns to the heating mode.
Stop condition 3
If for some reason the high pressure increases above the control
setpoint of the high pressure switch (S21HP/S22HP), the unit will
stop the defrost operation and return to the heating mode.