What is the first step when checking the pilot control setting on a pressure-reducing valve (PRV)?

Ensuring a pressure gauge is installed downstream of the valve is the correct first step when checking the pilot control setting on a pressure-reducing valve (PRV) because it allows for accurate monitoring of the pressure that the PRV is regulating. The pilot control system relies on feedback from the downstream pressure to maintain the desired outlet pressure.

By having a pressure gauge installed downstream, you can directly observe the pressure that the valve is controlling, confirming whether the PRV is functioning correctly and maintaining the set pressure. This step is essential to ensure proper assessment of the valve's performance and to make any necessary adjustments based on the readings.

In the context of the other steps, dropping pressure upstream or downstream without the proper gauge in place could lead to inaccurate assessments and potential safety hazards, as you wouldn't have a reliable means to gauge how the valve is operating. A pressure gauge upstream is also useful for monitoring the pressure entering the valve, but it does not provide feedback on the output pressure control, which is the focus when checking pilot control settings.