I recently switched from a Blichmann Top Tier burner (running natural gas) to a Blichmann Hellfire burner (also running natural gas). Initially, with the Blichmann NG conversion kit, I didn't have a problem getting a nice blue, powerful flame for several brews. I'm using a 10-foot hose of 3/8" ID coming out of standard North American residence (1/4 PSI or 8" WC).
My last brew was probably 3 months ago, and everything went perfectly. Last week, I fired up the burner for 10 gallons of a Blonde Ale. The natural gas flame was nice and blue, until I put the pot on. Almost immediately I got yellow tips on the flame. I tried a few things to correct the problem. I cleaned the air intake screen (which could have been clogged with dust). I cleaned the burner. I checked the hose. I adjusted the air intake to max.
After all that, when I ignited the burner, the flame looked perfect, but went back to yellow tips after I placed the pot. Since I was outside and pressed for time, I went ahead and completed the my brew day, and had to scrub a good amount of soot off of the bottom of my pot.
But at this point, I'm a bit unsure of how to proceed in diagnosing the problem. Yellow flame is due to there not being a proper air/fuel ratio. So, the problem is either too much fuel, or not enough air. My air intake is set to max (and I've removed the screen to eliminate that variable). I get blue flame until I add the pot, then yellow tips. When I turn down the fuel using the provided needle valve, I would expect the yellow tips to go away, since I'm reducing the fuel, but that's not what happens. The yellow tips stay present until the burner goes out because of lack of fuel.
What has me stumped is 1.) why doesn't turning down the fuel help? and 2.) why did it work fine 3 months ago and now I'm having problems?
Any suggestions or things I should try without spending much on re-doing my setup?
My last brew was probably 3 months ago, and everything went perfectly. Last week, I fired up the burner for 10 gallons of a Blonde Ale. The natural gas flame was nice and blue, until I put the pot on. Almost immediately I got yellow tips on the flame. I tried a few things to correct the problem. I cleaned the air intake screen (which could have been clogged with dust). I cleaned the burner. I checked the hose. I adjusted the air intake to max.
After all that, when I ignited the burner, the flame looked perfect, but went back to yellow tips after I placed the pot. Since I was outside and pressed for time, I went ahead and completed the my brew day, and had to scrub a good amount of soot off of the bottom of my pot.
But at this point, I'm a bit unsure of how to proceed in diagnosing the problem. Yellow flame is due to there not being a proper air/fuel ratio. So, the problem is either too much fuel, or not enough air. My air intake is set to max (and I've removed the screen to eliminate that variable). I get blue flame until I add the pot, then yellow tips. When I turn down the fuel using the provided needle valve, I would expect the yellow tips to go away, since I'm reducing the fuel, but that's not what happens. The yellow tips stay present until the burner goes out because of lack of fuel.
What has me stumped is 1.) why doesn't turning down the fuel help? and 2.) why did it work fine 3 months ago and now I'm having problems?
Any suggestions or things I should try without spending much on re-doing my setup?