Weber 1200 NG to LPG

[LMichaels]

Mike it's the orifices. They simply unscrew from the valve assembly. I have found dirt, corrosion and excess grease from the valve spool on them. A lady from Weber is who turned me on to checking there. Also there is no such thing as an LP or NG "elbow" a fitting is a fitting is a fitting. Like the burners they don't care and have no bearing of the gas type

 

[Mike Tee]

Mike it's the orifices. They simply unscrew from the valve assembly. I have found dirt, corrosion and excess grease from the valve spool on them. A lady from Weber is who turned me on to checking there. Also there is no such thing as an LP or NG "elbow" a fitting is a fitting is a fitting. Like the burners they don't care and have no bearing of the gas type

Awesome I will check the orifices. If that is the problem maybe it will resolve the orange flame on my silver as well.

this is the only reference I found. Any further advice? http://www.grill-repair.com/blog/20...-manifold-valve-orifice-burner-configuration/

Edit: as annoying as it is unscrewing the wingnut with pliers every time, I could also swap the front and back burner - that would reveal if the issue is jet/orifice or burner.

 

[LMichaels]

They will not swap. The crossover burner port will be on the wrong side. They only go one way. I doubt very much the orifice will cause the orange flame. Do the things I suggested. Thoroughly clean the burners and the spice screens. Inside and out. Look carefully for hairline crack(s) in the burners. I think that one burner of yours looks to have a crack. When cool you will not see it. Once flame is there it will open and disrupt even gas flow.
It's kinda tiring to give good advice and it keeps getting over thought or ignored. I think this is like the 3rd time I have given the same advice.

 

[Mike Tee]

They will not swap. The crossover burner port will be on the wrong side. They only go one way. I doubt very much the orifice will cause the orange flame. Do the things I suggested. Thoroughly clean the burners and the spice screens. Inside and out. Look carefully for hairline crack(s) in the burners. I think that one burner of yours looks to have a crack. When cool you will not see it. Once flame is there it will open and disrupt even gas flow.
It's kinda tiring to give good advice and it keeps getting over thought or ignored. I think this is like the 3rd time I have given the same advice.

I don’t understand. Your post above says “it’s the orifices”

 

[Mike Tee]

Hey Larry, it’s too bright to see if it has helped, but you were right, there was some web inside the tube deeper than the opening, so I didn’t see it at first. I will try it this eve to see if all works now.

 

[Bruce]

I do believe you can swap front and back burners. I do it every time I rehab a grill since flipping the tubes over reveals a much cleaner side than the side that originally up. That makes them easier to clean up nice and shiny. At least in my experience. the front and back burners are essentially identical parts.

 

[Mike Tee]

Update. I swapped north and south burners, and cleaned out the web inside (current south) burner.

Photos attached on High, Medium and Low. North burner is flameless on low heat.

still new burners suggested or something else, or nothing? It seems weird that the third burner wouldn’t Burn on low.

Then, same on the silver B for reference.

MT

 

[Mike Tee]

Silver B

 

[Bruce]

Mike, do you get same/similar results with the front and back burners swapped?

 

[Mike Tee]

Mike, do you get same/similar results with the front and back burners swapped?

the cleaned burner is way better. I didn’t think to test on low in this way before I swapped and I haven’t tested the cleaned burner back in it’s original spot in rear. I can try to do so soon.

 

[Mike Tee]

So - interesting. North burner back to north side. Two observations.

Much more orange flame than when it was on south.

Low burner still goes out on north side on low.

Trying with burner from NG now, but assume this isn’t solely a burner problem. What to do?

 

[Mike Tee]

Different north burner. Getting brighter outside - scrunched into the only shaded corner!

Seems cleaner on high. same problem on low.

 

[LMichaels]

Burners are burners. No difference between a NG or LP burner UNLESS the burners themselves contain the gas metering orifices. Which nothing Weber makes does. So the only change will be whether the burner you switch out is simply in better physical condition

 

[Mike Tee]

Burners are burners. No difference between a NG or LP burner UNLESS the burners themselves contain the gas metering orifices. Which nothing Weber makes does. So the only change will be whether the burner you switch out is simply in better physical condition

Yes, I understand. I am trying to differentiate from where these parts are coming from for context. The same with the elbow referenced earlier - I wanted it to be clear I hadn’t used the NG fitting.

the question for me is why the burner extinguishes on low. It’s not the physical condition of the burner, as I’ve now tried 3 different burners.

edit: I can live with this if it’s not indicative of a larger issue. I rarely use the back burner on low heat.

 

[Bruce]

Mike, from your testing, if I understand correctly, there is little change in performance when you swap burners. So, I think we can safely eliminate the burners as being the problem. Tracing backwards, we come to the orifice. Is there a blockage in the rear orifice preventing full flow to the burner? If not, it would seem the valve might be the problem. Past that, you are looking at the manifold itself but that is much less likely, but not impossible that something is inside the manifold preventing full flow to the rear burner.

I suppose your next step would be to swap the orifices between burners to see if the problem follows the orifice or if it stays at the rear burner.

 

[Mike Tee]

Mike, from your testing, if I understand correctly, there is little change in performance when you swap burners. So, I think we can safely eliminate the burners as being the problem. Tracing backwards, we come to the orifice. Is there a blockage in the rear orifice preventing full flow to the burner? If not, it would seem the valve might be the problem. Past that, you are looking at the manifold itself but that is much less likely, but not impossible that something is inside the manifold preventing full flow to the rear burner.

I suppose your next step would be to swap the orifices between burners to see if the problem follows the orifice or if it stays at the rear burner.

The orifice looked clear when I took it off, but like the burner maybe I didn’t look closely enough.

for reference, the back burner will stay on when on high with the others on low. And will go out when on low, regardless of setting of other burners.

I have spare jets from the NG, but they are L264F instead of L264. Is the difference the brass cone direction and orifice or is there more? I will try what you suggested above.

I was on hold with Weber while composing - he suggested it might be the crossover burner so is sending me a new one. Still hesitant to sell the silver b before I resolve this!

 

[Bruce]

I didn't think about the cross over tube being the problem, but I guess it might have an affect.

 

[Mike Tee]

I didn't think about the cross over tube being the problem, but I guess it might have an affect.

I think you’re right. I’ve used bbqs with a burnt out (Blown out?) crossover and the burner still ran on low. Looking after the kids so can maybe try again tomorrow am or after bed.

Thoughts on swapping a jet if orifice swap isn’t conclusive?

 

[Bruce]

Yah, I would try swapping orifices. It that doesn't change anything, you might have to look for an obstruction inside the manifold.

 

[LMichaels]

If the burner is extinguishing on low there is either something wrong with the valve itself, an improperly sized orifice (are these home drilled or factory from Weber?), or something wrong with the physical condition of the burner itself. Have you even thought about simply buying new burners and trying a new set of burners. I am getting the impression you're working very hard to make an easy job difficult