Discharge Pipe Protection Control - Daikin VRV II RXYQ8MY1K Service Manual

Si39-502A
4.3

Discharge Pipe Protection Control

This discharge pipe protection control is used to protect the compressor internal temperature
against a malfunction or transient increase of discharge pipe temperature.
[INV compressor]
HTdi>115˚C
or
Tp>140˚C
INV upper limit frequency:
1-step down from current
compressor frequency
Every 30 sec.
HTdi>115˚C
or
Tp>140˚C
HTdi>130˚C
HTdi>120˚C
or
for 90 sec.
or more.
INV62 Hz + OFF + OFF
[STD compressor]
Discharge pipe temp.
protection control not limited
Function
Each compressor performs the discharge pipe temperature protection control individually
in the following sequence.
Normal operation
&
In discharge pipe temp.
protection control
or
Discharge pipe
temperature standby (for
a period of 10 minutes)
• HTds>120˚C continues for 5 min. or more.
• HTds>135˚C
or
• Tp>140˚C continues for 10 min. or more.
• Tp>150˚C
10 min.
HTdi :Value of INV compressor discharge pipe
temperature (Tdi) compensated with
outdoor air temperature
Tp : Value of compressor port temperature
calculated by Tc and Te, and suction
HTdi<100˚C
superheated degree.
Tp<110˚C
Every 60 sec.
HTdi<110˚C
&
Tp<125˚C
HTdi>135˚C
HTdi>120˚C for 10 min. or more.
When occurring 3 times within 100 minutes,
the malfunction code "F3" is output.
HTds : Value of STD compressor discharge
pipe temperature ( Tds) compensated
with outdoor air temperature
Tp: Value of compressor port temperature
calculated by Tc and Te , and suction
superheated degree.
Applicable STD
compressor stops.
Protection Control
INV upper limit frequency: 1-step up
from current compressor frequency
71