Discharge Pipe Protection Control - Daikin VRV RXYQ72-384XAYCA Service Manual

Protection Control
6.3

Discharge Pipe Protection Control

This discharge pipe protection control is used to protect the compressor internal temperature
against an error or transient increase of discharge pipe temperature.
HTdi : Value of compressor discharge pipe temperature (Tdi) compensated with outdoor air temperature
Ti : Compressor body temperature
A : Maximum of HTdi and Ti
X (°C)(Y (°F)) : RXYQ72-120XA, RXYQ72-120XB
→115°C (239°F) (constant)
RXYQ144/168XA, RXYQ144/168XB
→Temperature determined by compressor rotation speed
X (°C)
110
105
100
A (°C) > X (°C)
(A (°F) > Y (°F))
After 30 seconds
3-step down
A (°C) > X (°C)
(A (°F) > Y (°F))
After 30
seconds
9-step down
A (°C) > X+5 (°C)
(A (°F) > Y+9 (°F))
A (°C) > X+10 (°C)
(A (°F) > Y+18 (°F))
21-step down
After 30 seconds
A (°C) > X+15 (°C)
(A (°F) > Y+27 (°F))
HTdi > 135°C (275°F)
OR
HTdi > 120°C (248°F)
continues for 10 minutes
Ti > 120°C (248°F)
continues for 5 seconds
Ti > 115°C (239°F)
continues for 10 minutes
97
Y (°F)
230
221
212
80 90
Upper limit compressor step:
max (Max. Step)
Normal control
After 20 seconds
Current
step
maintained
After 20 seconds
After 20 seconds
Compressor step: 1
Discharge pipe temperature
standby
(2 times within 100 minutes)
120
Compressor
rotation speed (rps)
9-step up
A (°C) < X–10 (°C)
(A (°F) < Y–18 (°F))
A (°C) < X–5 (°C)
(A (°F) < Y–9 (°F))
3-step up
Discharge pipe temperature standby
(3 times within 100 minutes)
Abnormal stop
(F3 is displayed)
SiUS342004EB
Part 4 Functions and Control