What must be done before a licensee can connect to an existing system installed by an unlicensed installer?

Before a licensee can connect to an existing system installed by an unlicensed installer, it is mandatory for the system to be pressure tested. This is a crucial step as pressure testing is used to ensure that the system does not have any leaks and is safe for operation. It verifies the integrity of the piping, valves, and other components under pressure, ensuring that they can withstand the operational pressures of the gas being used.

Conducting a pressure test helps to identify any weaknesses or failures within the system before the licensee connects their equipment. This enhances the overall safety of the system for future use. Inspecting the system through pressure testing also aligns with compliance and safety regulations, which are imperative in gas installations.

Other options, such as completely replacing the system or inspecting by a third party, may not be necessary if the integrity is confirmed through pressure testing. Additionally, issuing a new license is not relevant to the immediate need for verifying the installation prior to connection. Hence, the focus on pressure testing as the required step emphasizes the importance of safety and compliance in handling gas systems.