22
Installation Manual VMH SerieS Heat Controller, Inc.
When Using the Vacuum Pump
(For method of using a manifold valve, refer to its operation
manual.)
1. Completely tighten the are nuts, A, B, C, D, connect the mani-
fold valve charge hose to a charge port of the low-pressure
valve on the gas pipe side.
2. Connect the charge hose connection to the vacuum pump.
3. Fully open the Lo handle of the manifold valve.
4. Operate the vacuum pump to evacuate. After starting evacua-
tion, slightly loose theare nut of the Lo valve on the gas pipe
side and check that the air is entering(Operation noise of the
vacuum pump changes and a compound meter indicates 0
instead of minus)
5. After the evacuation is complete, fully close the Lo handle
of the manifold valve and stop the operation of the vacuum
pump. Evacuate for 15 minutes or more and check that the
compound meter indicates -29.92 inHg (-1x105Pa).
6. Turn the stem of the packed valve B about 45° counterclock-
wise for 6~7 seconds after the gas comes out, then tighten the
are nut again. Make sure the pressure display in the pressure
indicator is a little higher than the atmosphere pressure.
7. Remove the charge hose from the Low pressure charge hose.
8. Fully open the packed valve stems B and A.
9. Securely tighten the cap of the packed valve.
• When relocating the unit to another place, perform evacuation
using vacuum pump.
• Make sure the refrigerant added into the air conditioner is liquid
form.
Caution in handling the packed valve
• Open the valve stem until it hits against the stop. Do not try to
open it further.
• Securely tighten the valve stem cap with a spanner or the like.
• Valve stem cap tightening torque (see tightening torque table).
-29.92 inHg
Lo Handle Hi Handle
Air Purging