Yellow Flames from Range Surface Burner

[george7941]

Wolf gas range. Front right burner has yellow flames. Checked gas orifice (#170), not clogged. Air adjustment (brass tube slid towards or away from orifice) makes no difference. 

 

 

[Terry Carmen]

Check the burner tube for cobwebs or crud. If things are slowing down the mixture flow, it won't suck up enough air for a good flame.

 

[george7941]

Did that already. There was a small blob of burnt food in there and I cleaned it out. The tube is totally clear now.

[ECtoFix]

The fact STILL remains that  your fuel-to-air ratio at the burner ports is too rich.  Somehow, you're getting too little air into to the PRIMARY air inlet (where the valve enters the burner)..or too much gas for the air it's able to take in.

[Terry Carmen]

> Air adjustment (brass tube slid towards or away from orifice) makes no difference. 

Something isn't right. The air adjustment must to make a difference.

Since the gas pressure is correct (the LF burner looks fine), all I can think of is that it's the wrong gas orifice or there's something wrong with the burner.

There's too much gas or not enough air.

 

Edited October 22, 2020 by Terry Carmen

[ECtoFix]

8 hours ago, george7941 said:

Wolf gas range. Front right burner has yellow flames. Checked gas orifice (#170), not clogged. Air adjustment (brass tube slid towards or away from orifice) makes no difference. 

What is #170?  Is that an index number on a parts diagram?  Having no model number (for getting a parts diagram) isn't helpful.

Is this a new install or a stove that's been in use for awhile?  If the latter, did someone work on it recently and possibly had changed the orifice?

Is that stove LP or natural gas?

That yellow flame looks like what would happen if a LP stove somehow got a natural gas orifice installed.

[Terry Carmen]

3 hours ago, ECtoFix said:

What is #170?  Is that an index number on a parts diagram?

170 is the size for the 16,000 BTU burner on Natural Gas.

If this is on propane, it's the wrong orifice and needs a 109 for the outer ring and a 7 for the inner ring.

[george7941]

170 is the number embossed on the side of the orifice.Running on natural gas, was installed 9 years ago. No work at all has been done on this stove since it was installed.

As to too much gas, even when gas flow is throttled down with the control knob on the console and the flame is smaller, it is still just as yellow.

[Terry Carmen]

1 hour ago, george7941 said:

As to too much gas, even when gas flow is throttled down with the control knob on the console and the flame is smaller, it is still just as yellow.

Then all that's left is the burner. There's something clogging the venturi tube or the burner head.

 

 

[Budget Appliance Repair]

Check to make sure the head of the burner isn't warped - if any of the other burners are the same size, swap the heads from one to the other and see if the large flame is now on the other burner that you moved the RF burner heads to.

If the head isn't flat and sealing all the way around the burner base the gas not only comes out the slots where it is suppose to but all around the burner causing way to much gas and not controlled by just the burner slots where the flame should come out of.

From the picture it looks to me like all what should be nice blue individual flames coming out each slot like the LF burner are all merging together being a sign that the outer burner head is warped and not sealing around the circumference of the burner base leaving just each individual  slot for flames but a small gap all the way around.

Hopefully I explained that were you will understand what I'm trying to say.

[george7941]

If I remove the left and right burner heads and let the gas burn without the burner heads, the flame is still nice and blue on the left but yellow on the right

There is no venturi other than the cone shaped orifice, which discharges into a brass tube I mentioned earlier. The brass tube can be moved closer to or away from the orifice after loosening a setscrew. Right now there is a gap of about 3/8 in between the end of the brass tube and the tip of the orifice. The brass tube is about 3/4 in ID. Varying the gap does not affect the flame much.

[Jason Munson]

Just a guess but can you take the left burner and put it on the right and see if it does the same?

[george7941]

Switched the burners and the right side still produces the yellow flames. The left and right burners are identical.

[Budget Appliance Repair]

So now we know it's not the head that is warped.   With the cast iron head on, look around the outer burner head and the cast iron cap and see if you see a slight gap between the top of the aluminum burner head and the cast iron burner cap.

It could be the aluminum head with the burner ports that is warped not letting the cap seal all around the top.