GAUGES
Gauges must be used in the evacuation and charging. They will provide information on the operation of the system when troubleshooting.
A gauge sets consist of two gauges installed in a manifold with two valves and hoses to connect the gauges to the system. The left gauge (blue) is a compound device; it indicates pressure and also vacuum. The right gauge (red) indicates pressure only. The valves open a center port (yellow) to the left or right side respectively. Operation of the valves is only necessary when moving refrigerant or evacuating. With the valves closed, the gauges read the pressures of the connection points.
VENTING THE GAUGE SET
TO ATTACH TO A CHARGED SYSTEM
Before operating the compressor on a charged system vent the hoses for a few seconds by slacking the hose connections at the manifold body after connecting. This will prevent air trapped in the gauge hoses from entering the system.
DISCONNECTING GAUGES
Disconnecting the gauge set after running the system may be done by turning off the compressor and allowing the pressures to equalize on the gauges then rapidly unscrewing the hoses from the service ports.
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