Points Of Analysis; Method Of Use By Symptom; To Conduct Analysis - Daikin VRV Service Manual

Points of Analysis

5. Points of Analysis
5.1

Method of Use by Symptom

In the Case of Faulty Compressor
1. While the compressor is running:
2. While the compressor stops running:
In the Case of Malfunction of Cooling
In the Case of Malfunction of Heating
5.2 To Conduct Analysis
In order to collect or analyze the Checker data,
First of all, make Pass/Fail judgment on functional parts
For accurate data collection, be sure to check functional parts for any problem.
Example: Even though the thermistor showed a normal value at an ambient temperature, the
detection data got out of order with increasing temperature.
(Particularly, to collect data on products manufactured in many years ago, give consideration to
the example mentioned above.)
178
Compressor oil temp. > Evaporating temp. (Low pressure saturation temp.) + 10°C
Discharge superheated degree (Discharge pipe temp. − Condensing temp. (High pressure
saturation temp. ) > 10°C
(however, 5°C within 12 minutes after startup.)
Compressor oil temp. < 80°C (If this oil temp. reaches 80°C or more, the oil viscosity will be
degraded.)
Check whether or not suction superheated degree is on a wet trend.
(Check to be sure the control of outdoor unit EVs while in heating or that of indoor unit EVs
while in cooling.) ← (Check whether or not the EVs are throttled.)
Ambient temp. + 15°C < Oil temp. < 80°C (Pass/Fail judgment of crankcase heater)
Check to be sure the temperature detected by pressure sensor has reached and kept
constant at target pressure (evaporating temperature).
Check to be sure the temperature detected by the liquid pipe thermistor of indoor unit
reaches about 5 to 7°C, and furthermore the temperature detected by the gas pipe
thermistor is about 10°C.
In addition, check to be sure the opening degrees of indoor unit EVs are about 500 to 1000
pulses, except while in capacity control mode.
(While in capacity control mode, the EV opening degrees are controlled toward closing side.
Thus, the superheated degree will have an increasing tendency.)
If the indoor unit EVs have uniform and same opening degrees, outdoor units have output
control instructions. In this case, check to be sure the data on outdoor units.
Check to be sure the temperature detected by high pressure sensor has reached and kept
constant at target temperature (condensing temperature).
Check to be sure the temperature detected by the liquid pipe thermistor of indoor units
reaches about 38°C.
Check to be sure the opening degrees of indoor unit EVs are about 500 to 1000 pulses.
(If the EVs fully open (i.e., the opening degree is 2000 pulses (or approx. 1400 pulses for
R410A), refrigerant may be charged excessively or heating load may reach a high level.)
High pressure − Liquid pressure > 2 kg/cm
unit side, which cannot be checked on the Checker.
(Due to the flow characteristics of EVs, unless the differential pressure between the front
and rear of the valve is
2
at service ports on stop valve on the outdoor
2
2 kg/cm , the liquid is hard to flow.)
Service Checker Type3 Application Edition
Si30-408