LEAK TEST

LINE SET AND INDOOR COIL

NOTE Normally, the high pressure hose is connected to the liquid line port. How- ever, connecting it to the vapor port better protects the manifold gauge set from high pressure damage.

1CONNECT GAUGE SET

A Connect an HFC−410A manifold gauge set high pressure hose to the vapor valve service port.

B With both manifold valves closed, connect the LOW cylinder of HFC−410A refrigerant to the center port

of the manifold gauge set.

NOTE Later in the procedure, the HFC−410A container will be replaced by the nitrogen container.

B

NITROGEN

HFC−410A

HIGH

MANIFOLD GAUGE SET

OUTDOOR UNIT

VAPOR SERVICE VALVE

A

TO VAPOR

SERVICE VALVE

LIQUID LINE

SERVICE VALVE

2TEST FOR LEAKS

After the line set has been connected to the indoor unit and air conditioner, check the line set connections and indoor unit for leaks. Use the following procedure to test for leaks:

AWith both manifold valves closed, connect the cylinder of HFC−410A refrigerant to the center port of the manifold gauge set. Open the valve on the HFC−410A cylinder (vapor only).

BOpen the high pressure side of the manifold to allow HFC−410A into the line set and indoor unit. Weigh in a trace amount of HFC−410A. [A trace amount is a maximum of two ounces (57 g) refrigerant or three pounds (31 kPa) pressure]. Close the valve on the HFC−410A cylinder and the valve on the high pressure side of the manifold gauge set. Disconnect the HFC−410A cylinder.

CConnect a cylinder of dry nitrogen with a pressure regulating valve to the center port of the manifold gauge set.

DAdjust dry nitrogen pressure to 150 psig (1034 kPa). Open the valve on the high side of the manifold gauge set in order to pressurize the line set and the indoor unit.

EAfter a few minutes, open one of the service valve ports and verify that the refrigerant added to the system earlier is measurable with a leak detector.

FAfter leak testing disconnect gauges from service ports.

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XC17 SERIES

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Lennox International Inc Dave Lennox Signature Collection XC17 Air Conditioner Leak Test, Line SET and Indoor Coil