ICC Commercial Mechanical Practice Exam

A shutoff valve must be installed at the connection to each appliance where what condition exists?

1. More than one fuel-oil-burning appliance is installed

2. More than two fuel-oil-burning appliances are installed

3. A supply fuel line manifold is installed

4. No supply fuel line manifold is installed

The correct answer is: More than one fuel-oil-burning appliance is installed

The requirement for a shutoff valve to be installed at the connection to each appliance arises specifically when there is more than one fuel-oil-burning appliance present. This is a safety measure designed to control the fuel supply to each appliance independently. By having a shutoff valve at each connection, maintenance and emergency shutdowns can be performed on a specific appliance without disrupting the operation of others. This setup enhances safety and ensures compliance with industry standards and codes that dictate that any significant change in the number of appliances or configuration of the fuel supply system must include proper safety shutoff measures. While the other options discuss different scenarios related to the number of appliances or the presence of a supply fuel line manifold, they do not reflect the established requirement clearly linked with the installation of individual shutoff valves for safety in systems with multiple appliances.