Chicago Suburban
New Member
Bosch Aquastar tankless 1600 water heater fires on even when hot water not used. Then the unit automatically shuts off the gas after a minute. I have to re-lit the pilot and then the unit fires up and stays on for a minute and then shuts off gas again.
This is what happened. The pilot went out yesterday so I re-lit the pilot. I pressed the gas inlet button to light the pilot, and let it go after 30 seconds and the pilot stayed lit, however, the unit fired on right away as if someone was using the hot water. No one was using the water, so the unit should not fire on right after re-lighting the pilot. Then after a minute or so I heard a click and the gas automatically shut off. I had to reset the gas slider to off, wait a few minutes and then re-lit the pilot. The whole cycle repeated again and again. The unit fires on when the gas slider knob is at pilot-lighting position or anywhere "right" of that position. If I slide the gas knob slightly to the "left" of the pilot-lighting position, the pilot stays lit, but the unit does not automatically fire on at all.
Any ideas?
This is what happened. The pilot went out yesterday so I re-lit the pilot. I pressed the gas inlet button to light the pilot, and let it go after 30 seconds and the pilot stayed lit, however, the unit fired on right away as if someone was using the hot water. No one was using the water, so the unit should not fire on right after re-lighting the pilot. Then after a minute or so I heard a click and the gas automatically shut off. I had to reset the gas slider to off, wait a few minutes and then re-lit the pilot. The whole cycle repeated again and again. The unit fires on when the gas slider knob is at pilot-lighting position or anywhere "right" of that position. If I slide the gas knob slightly to the "left" of the pilot-lighting position, the pilot stays lit, but the unit does not automatically fire on at all.
Any ideas?
