Step 1. Following the lighting instruction label on the heater, proceed to light the pilot and allow to operate for three minutes. If the pilot will not stay lit, hold the pilot button (located on the gas valve) down during this test.
Step 2. Using a multimeter capable of measuring millivolts, connect one lead using an alligator clip to the copper sheath of the thermocouple. Use the second lead of the multimeter to probe the top terminal located at the back of the gas valve.
Step 3. With a meter reading of 13 millivolts or greater, rotate the knob of the combination thermostat/gas valve to the “OFF” position.
Step 4. The magnet should remain closed for a drop of at least 6 millivolts. You will hear a “snap” or “click” sound when the magnet opens; if you hear this sound prior to a drop of 6 millivolts, the magnet is out of specification and the gas valve should be replaced.