5GAS LINE BALL SERVICE VALVE
CAP | 1/4 TURN ONLY |
| COUNTERCLOCKWISE |
| FOR FULL OPEN |
| POSITION |
| VALVE STEM |
UNIT SIDE |
|
OF VALVE |
|
| PRESSURE TAP PORT |
| GAS LINE CONNECTION |
| CAP |
| BODY |
COOLING | HEATING |
CORE
b.Isolation hangers should also be used when refriger- ant lines are run in stud spaces or enclosed ceilings.
c.Where the refrigerant lines run through a wall or sill, they should be insulated and isolated.
d.Isolate the lines from all ductwork.
E.SERVICE VALVE OPERATION
BRASS LIQUID AND GAS LINE SERVICE VALVES
The Brass Liquid and Gas Line Service Valves are factory shipped in the seated position to hold factory charge. The pressure tap service port (when depressed) opens only to the field brazing side of the valve when the valve is in the seated position. The liquid line valve is not a back seating valve (see WARNING below).
▲! WARNING
Extreme caution should be exercised when opening the Liquid and Gas Line Service Valves. Turn valve stem counterclockwise only until the stem contacts the rolled edge. (See Figures 4 and 6) No torque is required.
BRASS GAS LINE BALL SERVICE VALVE
The Brass Gas Line Service Valve is shipped in the closed position to hold the factory refrigerant charge. The pressure tap service port (when depressed) opens only to the field brazing side when the valve is in the closed position.
The Gas Line Service Valve is full open with a 1/4 turn. See Figure 5.
BRAZING REFRIGERANT LINES
1.Remove lower access cover to access service valves.
2.Before brazing, remove plugs from external copper stub tubes. Clean internal and external surfaces of stub tubes prior to brazing.
3.Cut and fit tubing, minimizing the use of sharp 90° bends.
4.Insulate the entire gas line and its fittings.
5.Do NOT allow uninsulated liquid line to come in direct contact with bare gas line.
Installer’s Guide
6GAS LINE SERVICE VALVE
6.Precautions should be taken to avoid heat damage to the pressure tap valve core during brazing. It is recommended that the pressure tap port valve core be removed and a wet rag wrapped around the valve body.
NOTICE:
Use care to make sure that no moisture enters pressure tap port, while wet rag is being used.
NOTICE:
Precautions should be taken to avoid heat damage to basepan during brazing. It is recommended to keep the flame directly off of the basepan.
7.Use a Dry Nitrogen Purge and Brazing Alloy without flux when brazing the field line to the copper factory connection. Flow dry nitrogen into either valve pressure tap port, thru the tubing and out the other port while brazing.
8.Braze using accepted good brazing techniques.
LEAK CHECK
IMPORTANT:
Replace pressure tap port valve core before attaching hoses for evacuation.
After the brazing operation of refrigerant lines to both the outdoor and indoor unit is completed, the field brazed connections must be checked for leaks. Pressurize through the service valve ports, the indoor unit and field refrigerant lines with dry nitrogen to
SYSTEM EVACUATION
NOTE:
Since the outdoor unit has a refrigerant charge, the gas and liquid line valves must remain closed.
1.Upon completion of leak check, evacuate the refrigerant lines and indoor coil before opening the gas and liquid line valves.
2.Attach appropriate hoses from manifold gauge to gas and liquid line pressure taps.
NOTE:
Unnecessary switching of hoses can be avoided and com- plete evacuation of all lines leading to sealed system can be accomplished with manifold center hose and connecting branch hose to a cylinder of
3