Bard HAC421-AD040, HAC601-AD040, HAC481-BD040, HAC481-AD040, HAC601-BD040 Manual 2100-346

2.The tubing ends should be cut square. Make sure it is round and free of burrs at the connecting ends. Clean the tubing to prevent contaminants from entering the system.

NOTE: Do not make any tubing connection at indoor unit at this time. Make all brazing of joints and evacuate both suction and liquid line first.

3.Wrap a wet rag around the copper stub before brazing.

4.Flux the copper tube and insert into the stub. Braze the joint using an alloy of silver or copper and phosphorus with a melting temperature above 1,100° F for copper to copper joints. The phosphorus will act as a flux, therefore, no flux will be required.

A copper-silver alloy with a high silver content should be used when iron or steel material is involved in the joint. These alloys require the use of silver solder flux. Alloys containing phosphorus should not be used with iron or steel. Phosphorus reacts with the iron forming iron phosphate which is extremely brittle.

To further prevent the formation of copper oxide inside the tubing, dry nitrogen may be purged through the refrigerant system during brazing.

CAUTION

1.Brazing alloys with a melting temperature below 700° F should not be used. 2. Lead-tin or tin-antimony solders should not be used due to their low melting point and necessity for corrosive fluxes.

WARNING

Never purge or pressurize a system with oxygen. An explosion and fire will result.

5.After brazing, quench with wet rag to cool the joint and remove any flux residue.

6.Leak test all connections using an electronic leak detector or a halide torch.

7.Evacuate suction line and liquid line through outdoor unit base valves.

If orifice does not have to be changed, skip the instructions outlined further in Step 8 and proceed to Step 15.

8.Recover charge from the indoor unit.

A.Connect the suction line only to the indoor unit as outlined in Steps 15, 16, and 17.

B.Recover indoor unit and suction line unit charge through service port located on outdoor unit base valve.

9.Disassemble Flow Control Assembly by turning body hex.

10.If existing orifice has not dropped out of the body when disassembled, remove by using a pin or paper clip. Discard this original orifice.

11.Insert proper sized orifice fully into the flow control body with rounded “bullet” nose towards the unit as shown in Figure 4. Insure the orifice stays inserted in body before connecting mating half. See chart in the outdoor unit installation instructions for proper size.

CAUTION

Be sure there is no dirt introduced into the flow control – orifice assembly. Be sure to install the orifice with the bullet nose pointing in the proper direction as shown in Figure 4. Failure to do so will result in improper operation.

12.Thread assembly halves together by hand to insure proper mating of threads and tighten until bodies “bottom” or a definite resistance is felt.

13.Using a marker pen or ink pen, mark a line lengthwise from the union nut to the bulkhead. Then tighten an additional 1/6 turn (or 1 hex flat). The misalignment of the line will show the amount the assembly has been tightened. This final 1/6 turn is necessary to insure the formation of the leakproof joint.

14.Evacuate the suction line and indoor unit through the outdoor unit base valve before connecting all other tubing. Refer to section later in installation instructions for details on setting the proper refrigerant charge.

15.Remove (remaining) protector caps and plugs (if orifice was changed). Inspect fittings and if necessary carefully wipe coupling seats and threaded surfaces with a clean cloth to prevent the inclusion of dirt or any foreign material in the system.

Manual 2100-346 Page 7