Results of Air Shutter Adj on Water Heater

[howson]

I'd never given the "roar" I heard when the gas fired to heat the water much thought. After learning about the purpose for the air shutter and how to adjust it for the most efficient operation of the burner, I tinkered with it just to see (hear) what would happen. Below is the result. (Make sure and have your speakers on.)

Note that some water heaters do not have an adjustable air shutter, so YMMV.

Howard

[Country Campers]

Howard,

So when you moved the air shutter and the flame got quieter does that mean that it is adjusted to the optimum setting? Is there a gauge for this setting or is it done by ear?

Brian

[howson]

Howard,

So when you moved the air shutter and the flame got quieter does that mean that it is adjusted to the optimum setting? Is there a gauge for this setting or is it done by ear?

Brian

Ear and flame color, Brian, is what I did. The flame should be blue. If I remember correctly it's OK to have just a bit of yellow at the tips.

Note that adjusting the air shutter should be done after confirming 11" of water column from the regulator (with a 50% load on the system) and, if there's any suspicion of a problem, measuring the output pressure from the water heater's valve using it's test port. The test port is sometimes impossible to access, though, as galvanic corrosion can seize it shut. (Could a problem if an owner tries to force it open--and without the right test equipment the effort would be in vain, anyway.)

[StephenO]

From my keyboard 'research' on adjusting the air admittance, it indicated that you should only faintly hear the water heater running when you are about 5' - 10' away, and the flame should be mostly blue. When it's loud enough that you hear it at those distances, where it sounds like a jet engine, you need to adjust it. It's funny, I never gave it much thought until I read that, and after that point, I started hearing and paying attention to everyone else's water heaters in the campground that I can hear from several sites away. You just hear those water heater jets ready to take off, especially here at higher altitudes.