York H5CE090 User Manual

10. After the disc has been removed, burnish the external sur-

faces and clean the internal surfaces as outlined above.

The suction piping can now be brazed to the suction

connection on the evaporator coil while maintaining a

minimum flow of dry nitrogen.

Before brazing the suction line to the condensing unit;

1. Move the dry nitrogen supply to the access port on the suc-

tion service valve of the condensing unit.

2. Burnish the external surfaces and clean the internal sur-

faces of both the suction connection and the suction piping.

The suction line can now be brazed to the suction con-

nection on the condensing unit while maintaining the

flow of dry nitrogen.

After the liquid and suction lines have been installed,

the system should be evacuated and charged.

EVACUATION AND CHARGING

With the liquid and suction line service valves closed, connect a

vacuum pump through a charging manifold to the access ports

on both the liquid and suction line service valves.

Note:

The vacuum pump connection should be short and

no smaller than 3/8" O.D.

The refrigerant lines and the evaporator coil can now be evacu-

ated to 500 Microns without disturbing the charge in the con-

denser coil or the compressor.
After proper evacuation and dehydration, charge refrigerant

through the access port on the liquid line service valve allowing

the vacuum to draw in as much refrigerant as possible.

CAUTION: Do not charge liquid refrigerant through the com-

pressor suction connection.

CAUTION: Do not attempt to start the compressor without at

least 8 hours of crankcase heat or compressor

damage will occur.

To continue charging refrigerant, open the liquid and the suc-

tion line service valves fully. Turn the stem of the liquid service

valve clockwise 1/4 turn to open its access port for reading

pressure.
Start the compressor (after 8 hours of crankcase heat), turn the

stem of the suction line service valve clockwise

turn to open

its service port and continue to charge refrigerant gas through

this suction access port until you meet the conditions shown on

the charging curve, Fig. 8-10

Open the liquid and vapor line service valves fully to close their

access ports after the system has been charged.

Alternate Charging Methods

If you are starting a unit when the ambient temperature is

higher or lower than those shown in Fig. 8-10, either of the fol-

lowing methods may be used.

Method 1: Determine the total weight of the refrigerant for the

total system by adding the required charge for the

outdoor unit, the indoor unit and the refrigerant

lines using information in Tables 2 (Physical Data)

and 6 (Refrigerant Line Charge).

Using the charging procedures outlined above,

weigh the required amount of refrigerant charge

into the unit.

Method 2: Install a field supplied moisture indicating sight

glass in the liquid line between the filter-drier and

the evaporator coil.

Using the charging procedure outlined above,

charge refrigerant until the moisture indicating

sight glass is clear. Add approximately 1 extra

pound of refrigerant for the 090 and 120 or 3 extra

pounds for the 150 to assure a liquid refrigerant

seal at the expansion valve under all operating

conditions. Block the flow of the condenser air, if

necessary, to assure a head pressure of 280 psig

during the charging procedure.

Note:

The installer should return to the job to verify the

operating charge when the ambient temperature is

within the conditions shown in Fig. 8-10.

035-15407-002-B-0404

Unitary Products Group