A few days ago, we found our 2009 Navien NR-240A exhaust vent bird screen on the ground about 12 feet away from the end of the vent. Very odd, and has never happened before. I can't believe some neighbor kid is messing with us and it's hard to remove so I doubt birds or other animals are the cause.
(See update post below - it happened again, this time while my wife was in the backyard...)
The vent pipe is nominally horizontal and about three feet above ground. The screen had been originally installed with silicone sealant and it was a tight fit to put it back in.
This a.m., it was on the ground in about the same location.
Since the screen is mostly open area, it would take considerable internal pressure for it to "blow" out, and we have not heard any explosions. I suppose it could happen in the a.m. when the internal re-circ starts and we are still asleep.
The unit seems to be operating ok. It was serviced recently (warranty heat exchanger replacement) and immediately after the replacement we got a "flame loss" error code 12. On callback, the tech said the "low fire was really low" and he adjusted it so "both high and low are within spec, at the richer end of the range."
I'm thinking of installing a webcam to monitor it.
Anyone ever hear of vent screens blowing off? How likely is there to be an explosion in the vent pipe that doesn't cause significant destruction?!
(See update post below - it happened again, this time while my wife was in the backyard...)
The vent pipe is nominally horizontal and about three feet above ground. The screen had been originally installed with silicone sealant and it was a tight fit to put it back in.
This a.m., it was on the ground in about the same location.
Since the screen is mostly open area, it would take considerable internal pressure for it to "blow" out, and we have not heard any explosions. I suppose it could happen in the a.m. when the internal re-circ starts and we are still asleep.
The unit seems to be operating ok. It was serviced recently (warranty heat exchanger replacement) and immediately after the replacement we got a "flame loss" error code 12. On callback, the tech said the "low fire was really low" and he adjusted it so "both high and low are within spec, at the richer end of the range."
I'm thinking of installing a webcam to monitor it.
Anyone ever hear of vent screens blowing off? How likely is there to be an explosion in the vent pipe that doesn't cause significant destruction?!
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