Gas Furnace - Yellow Flame

[larryinnewyork]

Good Afternoon all.
Perhaps someone has had this problem in the past and can offer some advise.

I have a HEIL Furnace
3 Burners / 75,000 BTU
Installed 2008

Has been working flawlessly.

My concern:
Recently I have been noticing some 'yellow' on the burner flames.
Today, the flames had more yellow. Could be getting worse.

I took the burners out and cleaned them. They only had light surface rust.
Put back together and still had some yellow in flames.

I guess I'll have to have it looked at by Professional.

Question:
What will he do to eliminate/reduce yellow flame ? ? ?

I sure would like to fix myself if possible.
I could see no oxygen adjustment at flame locations.
I have no experience adjusting gas valve.

Any advise would be appreciated.
Safety is No. One.
Thank you.

Larry

 

[oldhp]

Did you check the flue pipe for any obstructions?

 

[gman2304]

I understand the flame tips should be a light yellow. I had my 20 year old Trane gas furnace checked back in the fall and the tech said mine was in good shape. The flame tips on mine are a light yellow.

 

[KzMitch]

Have you recently painted?
Paint fumes will cause yellow flame.

 

[larryinnewyork]

Did you check the flue pipe for any obstructions?
No obstructions.

Have you recently painted?
Yes. Gutter brackets are drying (in basement) as we speak.
But, this furnace takes air from the outside.

Still, I wonder if painting is the cause.
I've been spray painting for 1 Month (off & on). Around the time the yellow flames started.

I'll hold off on anymore painting and watch what happens.

Any other suggestions ? ? ?

 

[mtndew_dad]

Do you have any other gas appliances, and if yes, how does the flame look?

 

[Cujet]

Quite simply, it's running rich. As mentioned above, it could be a restriction in airflow. Such as intake or exhaust restriction. Or, it could be that the metering orifice has eroded slightly and is larger than it was when new. In this case, simply replace the orifice. Or, gas pressure may have changed, creating slightly more gas flow.

 

[larryinnewyork]

The results are in.

Thanks everyone for their suggestions and advise.

Apparently the spray-painting I was doing in the basement was affecting the furnace burner flames.

I stopped the painting and (2 days later) the flames came back to an acceptable blue color.

The cloths-dryer burner looked good all this time.
Perhaps the furnace has a more 'sensitive' burner.

In conclusion, if a gas appliance burner does not look right, ask yourself if anything may be affecting the oxygen requirements of that appliance.