What method can be used to check for a leak without a meter?

The method that allows for checking for a leak without a meter, such as a manometer, is to use a soap solution to check connections. This approach is effective because it involves applying a soap solution to the joints and connections of the gas system. If there are any leaks present, small bubbles will form at the site of the leak, indicating that gas is escaping. This method is a simple, reliable, and widely used technique that does not require specialized equipment beyond the soap solution itself.

Using visual inspection of all appliances primarily helps in spotting obvious issues or wear but may not detect small or hidden leaks. Listening for gas escaping can be unreliable; it may not be practical in a noisy environment or if the escaping gas is at a very low pressure. Although attaching a manometer between the inlet and the first regulator is a valid technique for measuring pressure changes, it requires tools and not just a straightforward way of detecting a leak without any specialized equipment. Thus, the soap solution method stands out as the best answer for checking for leaks without needing meters.