Daikin ERLA03DAV3, Руководство по установке для специалистов, Страница: 65 / 192

7 | Piping installation
Installer reference guide
65
ERLA EHFZ03S18DJ3V
Daikin Altherma 3 R F
4P596821-1A – 2020.05
7.4 Checking the refrigerant piping
7.4.1 About checking the refrigerant piping
The outdoor unit's internal refrigerant piping has been factory tested for leaks. You
only have to check the outdoor unit's external refrigerant piping.
Before checking the refrigerant piping
Make sure the refrigerant piping is connected between the outdoor unit and the
indoor unit.
Typical workflow
Checking the refrigerant piping typically consists of the following stages:
1 Checking for leaks in the refrigerant piping.
2 Performing vacuum drying to remove all moisture, air or nitrogen from the
refrigerant piping.
If there is a possibility of moisture being present in the refrigerant piping (for
example, water may have entered the piping), first carry out the vacuum drying
procedure below until all moisture has been removed.
7.4.2 Precautions when checking the refrigerant piping
INFORMATION
Also read the precautions and requirements in the following chapters:
▪
"1 General safety precautions" [ 4 6]
▪
"7.1 Preparing refrigerant piping" [ 4 52]
NOTICE
Use a 2-stage vacuum pump with a non-return valve that can evacuate to a gauge
pressure of −⁠100.7 kPa (−⁠1.007 bar)(5 Torr absolute). Make sure the pump oil does
not flow oppositely into the system while the pump is not working.
NOTICE
Use this vacuum pump for R32 exclusively. Using the same pump for other
refrigerants may damage the pump and the unit.
NOTICE
▪
Connect the vacuum pump to the service port of the gas stop valve.
▪
Make sure that the gas stop valve and liquid stop valve are firmly closed before
performing the leak test or vacuum drying.
7.4.3 To check for leaks
NOTICE
Do NOT exceed the unit's maximum working pressure (see "PS High" on the unit
name plate).