LG Electronics MFL39817303 installation manual Air Purging, Air purging with vacuum pump

Page 25

Installation

AirPurging

Air purging

The air and moisture remaining in the refrigerant system have undesirable effects as indicated below.

1.Pressure in the system rises.

2.Operating current rises.

3.Cooling(or heating) efficiency drops.

4.Moisture in the refrigerant circuit may freeze and block capillary tubing.

5.Water may lead to corrosion of parts in the refrigeration system.

Therefore, after evacuating the system, take a leak test for the piping and tubing between the indoor and outdoor unit.

Air purging with vacuum pump

1. Preparation

Check that each tube(both liquid and gas side tubes) between the indoor and outdoor units have been properly connected and all wiring for the test run has been completed. Remove the service valve caps from both the gas and the liquid side on the outdoor unit. Note that both the liquid and the gas side service valves on the outdoor unit are kept closed at this stage.

2. Leak test

Connect the manifold valve(with pressure gauges) and dry nitrogen gas cylinder to this service port with charge hoses.

Be sure to use a manifold valve for air purging. If it is not available, use a stop valve for this purpose. The "Hi" knob of the manifold valve must always be kept close.

Pressurize the system to no more than 150 P.S.I.G. with dry nitrogen gas and close the cylinder valve when the gauge reading reached 150 P.S.I.G. Next, test for leaks with liquid soap.

To avoid nitrogen entering the refrigerant system in a liquid state, the top of the cylinder must be higher than its bottom when you pressurize the system. Usually, the cylinder is used in a vertical standing position.

1. Do a leak test of all joints of the

 

 

 

 

tubing(both indoor and outdoor)

 

Manifold valve

and both gas and liquid side

Indoor unit

service valves.

 

 

 

 

Bubbles indicate a leak. Be sure to

 

Lo

Hi

 

 

 

 

 

wipe off the soap with a clean

 

 

 

 

cloth.

 

Charge hose

 

 

2. After the system is found to be free

Outdoor unit

 

 

 

 

 

 

 

 

 

of leaks, relieve the nitrogen

 

 

 

 

pressure by loosening the charge

 

Nitrogen gas

 

 

hose connector at the nitrogen

 

cylinder(in vertical

 

 

cylinder. When the system pressure

 

standing position)

 

 

 

 

 

 

is reduced to normal, disconnect

 

 

 

 

the hose from the cylinder.

 

 

 

 

 

 

Installation Manual

25

ENGLISH

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Contents Room Air Conditioner Table of Contents Installation Instructions Be sure not to do Be sure to follow the instruction No installation may cause a fire and electrical shockIt may cause injury or an accident Operation Otherwise, it may cause dispute with the neighbors Otherwise, it may cause water leakageOtherwise, it may cause vibration or water leakage Otherwise, it may do harm to your healthFeatures Symbols used in this ManualInstallation Tools Installation PartsRead carefully, and then follow step by step Installation Map Indoor unit Select the best LocationOutdoor unit Piping Length and Elevation Drill a Hole in the Wall Fixing Installation PlateType Cutting Tubes Flaring WorkBurrs removal Putting nut onCheck Connecting the PipingIndoor Foamed polyethylene or equivalent is recommendedLbf .ft Indoor unit installationFor left rear piping Piping for passage through piping hole Bad case Good caseHow to use the front panel Connecting the CablesOutdoor Move the link upward and close the front panelFront panel removing Refix the cover control to the original position Connect the wires to the terminals onWith the screw For strand wiring How to connect wiring to the terminalsConnecting cable To check the drainage Checking the DrainageDrain piping Pour a glass of water on the evaporatorForming the Piping Air purging Air PurgingAir purging with vacuum pump Evacuation Soap water methodFinishing the job If bubbles come out, the pipes have leakageTest Running Prepare remote controllerSettlement of outdoor unit Evaluation of the performancePump Down Pump Down ProcedureSelecting the locationOutdoor Unit Installation guide at the seasideMemo Room Air Conditioner No. MFL39817303