9
Ultra-Aire SD12 Installer’s & Owner’s Manual
FOR HVAC INSTALLER ONLY
9. Carefully torque the flare nuts to the corresponding flare fittings
on the condensing unit valves.
• Torque the liquid line flare nut to 13.3 ft-lbs.
• Torque the suction line flare nut to 30.1 ft-lbs.
10. Reinstall service valve cores and caps.
Note
– Alternately, the stubs with the flare fittings can be connected
to the condensing unit before brazing the line set. In this case a field
provided heat shield, such as a wet rag, must be placed over the
flare fittings and valves on the condensing unit to protect them from
heat damage. The service valve cap and core should be removed
before brazing near stub tubes.
3.5 Leak Test Line Set and Dehumidifier
Manifold Gage Set - When checking the system charge, use a
manifold gage set that features low loss anti-blow back fittings.
Manifold gage set used with HFC-410A refrigerant systems must
be capable of handling the higher system operating pressures. The
gages should be rated for use with high side operating pressures
of 0 – 800 psig and low side operating pressures of 30 inches of
vacuum to 250 psig. Dampened gages or anti-flutter gages are
recommended. Gage hoses must be rated for use at up to 800 psig
of pressure with a 4000 psig burst rating.
IMPORTANT!
THE ENVIRONMENTAL PROTEC-
TION AGENCY (EPA) PROHIBITS THE INTENTIONAL VENTING OF
HFC REFRIGERANTS DURING MAINTENANCE, SERVICE, REPAIR
AND DISPOSAL OF APPLIANCE. APPROVED METHODS OF
RECOVERY, RECYCLING OR RECLAIMING MUST BE FOLLOWED.
WARNING!
WHEN USING A HIGH PRESSURE GAS
SUCH AS DRY NITROGEN TO PRESSURIZE A REFRIGERATION OR
AIR CONDITIONING SYSTEM, USE A REGULATOR THAT CAN CON-
TROL THE PRESSURE DOWN TO 1 OR 2 PSIG.
IMPORTANT!
LEAK DETECTOR MUST BE CA-
PABLE OF SENSING HFC REFRIGERANT.
WARNING!
REFRIGERANT CAN BE HARMFUL IF
IT IS INHALED. REFRIGERANT MUST BE USED AND RECOVERED
RESPONSIBLY. FAILURE TO FOLLOW THIS WARNING MAY RESULT
IN PERSONAL INJURY OR DEATH.
1. Connect the HFC-410A manifold gage set high pressure hose to
the service port on the suction gas line.
Note
– Connecting the high pressure hose to the service port on
the gas line will protect the manifold gage set from high pressure
damage during leak testing. Cap liquid line service port.
2. Make sure all of the valves on the manifold gage set are closed.
Connect a cylinder of HFC-410A refrigerant to the center port of
the manifold gage set.
3. Position the HFC410A refrigerant cylinder to deliver vapor only.
Open the valve on the HFC-410A refrigerant cylinder.
4. Open the high pressure side of the manifold gage set to allow
HFC-410A into the line set and dehumidifier. Weigh in a trace
amount of HFC-410A [A trace amount is a maximum of two
ounces (57g) of refrigerant or 3 PSI]. Close the valve on the
HFC-410A cylinder and the valve on the high pressure side of the
manifold gage set.
5. Disconnect the HFC-410A refrigerant cylinder from the manifold
gage set.
6. Connect a cylinder of dry nitrogen with a pressure regulating
valve to the center port of the manifold gage set.
7. Adjust the dry nitrogen pressure regulator to 150 psig. Open the
valve on the high pressure side of the manifold gage set to
pressurize the line set and dehumidifier.
8. Close the valve on the dry nitrogen cylinder. Close the valve on
the high pressure side of the manifold gage set.
9. Allow the system to rest for a few minutes.
10. Check all (brazed and threaded) joints for leaks using a leak
detector designed to sense HFC refrigerants.
11. After leak testing is complete, disconnect the dry nitrogen cylin-
der from the center port of the manifold gage set and discon-
nect the high pressure hose of the manifold gage set from the
suction gas line service port.
LOW
HIGH
MANIFOLD GAUGE SET
NITROGEN
HFC-410A
TO VAPOR
SERVICE VALVE
OUTDOOR UNIT
3-WAY VALVE
2-WAY VALVE
LIQUID LINE STUB
GAS LINE STUB
SERVICE VALVE CAPS
VALVE ROD CAPS
VALVE STEMS
FIGURE 9
FIGURE 10: LEAK CHECK
Содержание 4033170
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