Discharge Pipe Protection Control - Daikin VRV II-Q RQYQ8-48PY1B Service Manual

Detailed Control Functions

2.5.3 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.
In case of multi-outdoor-unit system, each outdoor unit performs this control individually in the following
sequence.
[INV. compressor]
HTdi > 115 ˚C
INV. compressor
1 step down
Compressor
62Hz + ON + OFF
Compressor
62Hz + OFF + OFF
Restart standby: 10 minutes
(2 times per 100 minutes at max.)
[STD. compressor]
In case of multi-outdoor-unit system, each outdoor unit performs this control individually in the following sequence.
Normal operation
54
Normal operation
(Without preconditions)
Current step maintained
•HTdi > 115 ˚C
&
•After 30 seconds
HTdi > 120 ˚C continues for 90 seconds
HTdi > 120 ˚C continues for 90 seconds
•HTdi > 135 ˚C
OR
•HTdi > 120 ˚C continues for 10 minutes
• HTds > 120˚C continues for a period of
OR
continuous 5 min. or more
• HTds > 135˚C
10 min.
HTdi: Value of INV. compressor discharge pipe
temperature compensated with outdoor
air temperature
HTdi < 100 ˚C
•HTdi < 115 ˚C
&
•After 20 seconds
(Without preconditions)
Discharge pipe temperature
standby 3 times per 100 minutes
Stop due to error
F3
(" " displayed)
HTdS: Value of STD compressor discharge
pipe temperature (Tds) compensated
with outdoor air temperature.
SiBE341027
INV. compressor 1
step up
STD compressor stops
Function