It should be noted that you do not have to operate a burner at its maximum output for a given furnace, but rather there is a maximum amount of fuel and combustion air that can be introduced into a given furnace size that will fully combust, and any additional fuel or air added beyond that point will actually operate at a lower temperature.
What this means is that you can trade off melt time for lower fuel usage (lower gal/hr burn rate), ie: I can melt 20 lbs of aluminum in 12 minutes at a 2.6 gal/hr burn rate, but you can just as easily melt 20 lbs of aluminum at a much lower fuel flow, it will just take more time to reach pour temperature of about 1350 F.
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What this means is that you can trade off melt time for lower fuel usage (lower gal/hr burn rate), ie: I can melt 20 lbs of aluminum in 12 minutes at a 2.6 gal/hr burn rate, but you can just as easily melt 20 lbs of aluminum at a much lower fuel flow, it will just take more time to reach pour temperature of about 1350 F.
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