Press the ON/OFF key to power on the 725A. All LED’s will flash as the unit initializes. LED’s will turn on sequentially as the 725A auto zeroes. When the green LED above the ON/OFF switch flashes and a tick is heard the 725A is ready for use. Remove the sensor cap from the top of the 725A.

Trace gas lines, fittings, tanks, and containers for leaks. Once a leak above 40ppm is detected the 725A tick and green LED flash rate will increase. If the leak reaches 500ppm or above the red LEDs will illuminate accordingly (see below). To turn the 725A off, press and hold the ON/OFF key down for approximately 5 seconds.

In a clean air environment, press the ON/OFF key to turn the 725A on. All LED’s will flash as the unit initializes and auto zeroes. When the green LED above the ON/OFF switch flashes and a tick is heard the 725A is ready for use. Trace gas lines, fittings, tanks, and containers for leaks. Approach suspected leak areas with the sensor. When a leak above 40ppm is detected the 725A tick and green LED flash rate will increase.

When the tick rate increases press and release the ON/OFF key to nullify the tick and continue to approach the suspected leak area with the sensor. Continue to nullify the tick when the rate increases until the location of the leak are found. If the tick slows or stops on its own the concentration level has decreased. Move back in the opposite direction to find the leak again. Depending on the concentration of the leak level LED’s will illuminate accordingly.