SYSTEM VACUUMING AND CHECK FOR LEAKS
Fig. 10
It is first necessary to purge the air from the system with a vacuum pump. Both connections
and gauges must be adapted to R417A (or R22). Make sure the vacuum pump is in good
working condition.
а
) Remove the plugs of the outdoor unit two and three-way valves, as well as of the service
valve. Check if both valves of the outdoor unit are closed;
b) Connect the vacuum pump to the service valve;
c) After opening the valve plug the pump and let it run. It shall make vacuum for about 20-25
minutes.
d) Check whether the pressure gauge indicates pressure equal to 1 bar (or -76 cm Hg);
e) Close the pump valve. Make sure that the pressure gauge arrow does not move for at least 5
minutes. If the arrow is moving it means that within the system penetrates air and it shall be
necessary to check all connections. After finding and fixing the leak repeat the procedure from
start.
f) Turn off the pump and remove the hose connected to the service valve.
g) Open completely the two and three-way valves using Allen key.
h) Screw and tighten the valve plugs.
i) Check for refrigerant leaks with appropriate detector.
Fig. 11
10
