Inspecting The Refrigerant Amount - Daikin GYEQ20AN Service Manual

Inspecting the Outdoor Unit

1.27 Inspecting the Refrigerant Amount

Determine whether refrigerant is undercharged or overcharged based on the criteria given in the
following table:
Standard pressure range
Run mode
High-side pressure
Low-side pressure
Outdoor air temperature
1. Pressurize the refrigerant system to 4.0 MPa by charging N2 gas from the high/low pressure
2. After inspection, completely wipe off the soap solution to prevent rust.
3. Check the drain level in the compressor drain part.
[Checklist for early detection of refrigerant leak spots]
• Check for any spots where refrigerating machine oil is leaking.
• Check if a significant amount of refrigerating machine oil is collected in the compressor oil
• Check the stop valve and servicing port operating portion for any problems.
• Check the fusible plug of the receiver tank for any problems.
• Check the compressor flange tightening portions for any problems.
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Checking whether refrigerant is undercharged or overcharged
Measuring points Run mode
Cooling
Undercharged
Heating
Cooling
Overcharged
Heating
Checking for refrigerant leaks
side servicing port, and check for any leaks using a soap solution.
reservoir.
In a steady state during operation, the number of pulses
from EV4 is higher than 70, and the temperature
measured on the copper pipe surface, [T1]-[T2], is lower
than 2°C.
In a steady state with all indoor units running, the number
of pulses from EV1 is equal to or higher than 480.
Refrigerant pressure is excessively high.
(Beyond the standard pressure range specified below.)
Heating does not work even though the high-side
pressure is high and the engine speed stays low.
Cooling
2.0 to 3.4 MPa
0.6 to 1.1 MPa
21 to 35°C
SiAUY361411EA
Measured value
Heating
2.4 to 3.6 MPa
0.2 to 1.1 MPa
-10 to 21°C
Parts Inspection