Daikin FTKE25BVMT [196/268] Purging air and checking gas leakage

ED12-321A Outdoor Units

Installation Manual 191

Purging Air and Checking Gas Leakage

● If using additional refrigerant, perform air purging from the refrigerant pipes and indoor unit using a vacuum pump, then

charge additional refrigerant.

● Use a hexagonal wrench (4 mm) to operate the shut-off valve rod.

● All refrigerant pipe joints should be tightened with a torque wrench at the specified tightening torque.

Do not mix any substance other than the specified

refrigerant (R-22) into the refrigeration cycle.

WARNING

Refrigerant gas leaks during air purging, ventilate the

room as soon as possible.

WARNING

Use a vacuum pump for R-22 exclusively. Using the same vacuum pump for different refrigerants may damage the

vacuum pump or the unit.

To prevent air pollution, a vacuum pump should be used for air purging wherever possible.

(1) Connect projection side (on which worm pin is pressed) of charging hose (which comes from gauge manifold) to

gas shut-off valve’s service port.

(2) Fully open gauge manifold’s low-pressure valve (Lo) and completely close its high-pressure valve (Hi).

(High-pressure valve subsequently requires no operation.)

(3) Apply vacuum pumping. Check that the compound pressure gauge reads –0.1 MPa (–76 cm Hg). Evacuation for

at least 1 hour is recommended.

(4) Close gauge manifold’s low-pressure valve (Lo) and stop vacuum pump.

(Leave as is for 4-5 minutes and make sure the coupling meter needle does not go back.

If it does go back, this may indicate the presence of moisture or leaking from connecting parts. After inspecting all

the connection and loosening then retightening the nuts, repeat steps 2 – 4.)

(5) Remove covers from liquid shut-off value and gas shut-off valve.

(6) Turn the liquid shut-off valve’s rod 90 degrees counterclockwise with a hexagonal wrench to open valve.

Close it after 5 seconds, and check for gas leakage.

Using soapy water, check for gas leakage from indoor unit’s flare and outdoor unit’s flare and valve rods.

After the check is complete, wipe all soapy water off.

(7) Disconnect charging hose from gas shut-off valve’s service port, then fully open liquid and gas shut-off valves.

(Do not attempt to turn valve rod beyond its stop.)

(8) Tighten valve lids and service port caps for the liquid and gas shut-off valves with a torque wrench at the specified

torques. See “3 Refrigerant Piping” in “Outdoor Unit” for details.

WARNING