New York City Refrigeration License Exam I Practice

The key idea is to prevent refrigerant loss when you connect or disconnect the hoses. Low loss fittings are designed with built-in shutoff features that seal automatically as you disconnect, so refrigerant stays in the system and the charge isn’t wasted. This is especially important when using a manifold gauge set for testing, evacuating, charging, or recovering, because disconnecting hoses without a seal would let refrigerant escape and waste refrigerant, increase costs, and create environmental hazards.

Standard hose clamps only secure the hose onto a fitting and don’t prevent gas from escaping when you break the connection. Quick-release couplings offer speed but can still leak if not fully closed or sealed, so they don’t reliably minimize loss. Pressure relief valves are safety devices to vent if pressure gets too high; they’re not protections for hose connections during normal service.