Energy Tech Laboratories DSH installation instructions Separation Of Units

FORM 145.32-IOM1 (908)

SEPARATION OF UNITS

The 2 through 5 ton units are provided with refrigerant shut-off valves to allow the evaporator and condenser sections to be field split - without the necessity of re- claiming the entire unit refrigerant charge.

The evaporator and condenser sections may be sepa- rated by performing the following procedure:

1.Close all refrigerant shut-off valves, on both suction and liquid lines. There are four valves in a single compressor model, and a total of eight valves in the dual compressor models. Valves are not a back- seating design. Caps are wrench tight. Remove caps and turn stem clockwise to seat in the closed position.

2.Use the valve access ports to reclaim the refrigerant trapped in the lines between the pairs of shut-off valves.

3.Cut the refrigerant line sections between the pairs of shut-off valves. It is recommended to make this out where accessibility is greatest - in the condensing section of the unit. This will allow best access for reconnection, or attachment of an extended line set in the case of a split system.

4.Remove the interconnecting wiring between the evaporator and condenser electrical panel. Dis- connect the wire terminations in the condenser electrical panel, and pull the excess wire into the evaporator panel.

5.Remove the threaded wire bushing connecting the two electrical panels.

6.Remove the unit top-joining strip; take care to re- move only those screws which attaches the joining strip to the evaporator and condenser cabinets.

7.Remove the two side cross-member angles.

8.Carefully pull the evaporator section away from the condenser section. Take care not to damage the short lengths of refrigerant tubing extending into the condenser section.

The separated evaporator and condenser modules may now be individually moved to the proposed installation site for re-assembly, or separately located for split ap- plications.

INTERCONNECTING REFRIGERANT TUBING - SPLIT INSTALLATION

After the evaporator and condenser sections have been mounted, the interconnecting refrigerant tubing can be fabricated. Line sizing recommendations shown in the accompanying table are suitable for most applications. Consult sales office for applications outside the speci- fied guidelines.

Route refrigerant tubing for minimum linear length, and minimum number of bends and fittings. Use long radius elbows for all 90-degree bends, except oil traps. Traps should be constructed from short radius street elbows, in order to keep the trap as small as possible. All brazing should be done using a 2 to 8 psig dry nitrogen purge flowing through the pipe being brazed.

Once the brazing operation of refrigeration lines is com- pleted, the field-brazed connections must be checked for leaks. Pressurize the system through the shut-off valve ports with dry nitrogen to a minimum of 400 psig. Use soap bubbles or alternate methods of leak-checking all field brazed joints. After completion of the leak check, evacuate the interconnecting lines to hold a 350-micron vacuum. If gauge pressure rises above 500 microns in one minute, then evacuation is incomplete or the system has a leak.

Additional refrigerant (R-410A) must be added to the system due to the extended refrigerant lines. Calculate the amount of additional refrigerant required as fol- lows:

1. 5/16 in OD liquid line - add 0.40 oz per linear foot

2. 3/8 in OD liquid line	- add 0.60 oz per linear foot
3. 1/2 in OD liquid line	- add 1.20 oz per linear foot
4. 5/8 in OD liquid line	- add 1.80 oz per linear foot

8 JOHNSON CONTROLS