Leak Test Line Set and Indoor Coil
IMPORTANT
Leak detector must be capable of sensing HFC refrigerant.
CONNECT GAUGE SET
A Connect an HFC−410A manifold gauge set high pressure hose to the
vapor valve service port.
LOW
NOTE , the high pressure hose is connected to the liquid
line port. However, connecting it to the vapor port better protects the manifold gauge set from high pressure damage.
BWith both manifold valves closed, connect the cylinder of HFC−410A
refrigerant to the center port of the manifold gauge set.
NOTE
HFC−410A container will be replaced by the nitrogen container.
B
HIGH |
MANIFOLD GAUGE SET |
OUTDOOR UNIT |
A |
TO VAPOR |
SERVICE VALVE |
NITROGEN
HFC−410A
Figure 12. Manifold Gauge Set Connections for Leak Testing
TEST FOR LEAKS
After the line set has been connected to the indoor and outdoor units, check the line set connections and indoor unit for leaks. Use the following procedure to test for leaks:
1.With 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).
2.Open 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.
3.Connect a cylinder of dry nitrogen with a pressure regulating valve to the center port of the manifold gauge set.
4.Adjust 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.
5.After 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.
6.After leak testing disconnect gauges from service ports.
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