Need help with low flames

[ProxyGenesis]

Hi all, I am looking for some troubleshooting help with my 20 year old Genesis 1000. I recently inheriteted this grill and moved into a house that had a natural gas supply line already installed. I hooked up the grill and turned all burners to High and yet I can barely see low blue flames on all of the burner tubes. The grill has a hard time reaching 400 degrees after 15-20 minutes. I checked the supply connection making sure the shut off valve was fully open. I lightly scrubbed the burner tubes but it appears they are fairly clean. I see low blue flames on all 3 burner tubes. I don't smell gas leaking but would like info on how best to do a leak test. Any other suggestions or tips would be greatly appreciated. Thanks!

 

[homesmoke]

Are you sure that it is indeed a natural gas setup?
Propane spec'ed orifices are way smaller than the natural gas size, for a given BTU burner, and will run smaller flames.
If you have propane orfices and feed it natural gas, you will get the condition you described.

Orifices are numbered, and can be identified as to how many BTU's that particular number orifice will deliver, whether on propane or natural gas, so cross reference which you have. They are mounted on the end of the valve assembles, and fit into the end of each of the burner tubes. Any gas supply house will have a chart that will show you which # orifice will be needed to achieve the BTU rating you desire, whether propane or natural gas.

Orifices clean?
Air screens clear?
Air adjustments proper?
Gas flowing from hose the same volume at both ends? House supply output at the valve, and where hose attaches to manifold checked?
Spiders and other creepy crawlies, can clog manifolds, orifices, burners, and hoses, especially if grill sat for a long time.
May just need some compressed air to clear.

Good luck.

 

[ProxyGenesis]

Thank you! I bet you are on to something with it being clogged up a bit. This sat in a shed for several years and was full of all kinds of things. I will try and clean out the lines( or just replace them). It definitely is a natural gas grill though because that’s how it was previously connected and working well. Thanks.

 

[BuffettFan]

Agree with everything homesmoke said.
One addition, if the grill has a regulator, it could be bad as well.
I had the same condition on my Jenn Air LP gasser and after complete disassembly, cleaning and reassembly still had the problem. A properly sized (by total BTU output of the grill) replacement regulator solved the problem.
Good Luck!

 

[jpbsarris]

Natural gas grills don't use a regulator like LP models do. The gas pressure is regulated at the utility meter. That said it could be a low pressure issue with your meter pressure regulator. Your utility company can check it out for you. It should be around 7 water column inches. If you are getting a mostly blue flame it's not likely an issue with the burner tubes being restricted. The flame would be yellow if it was not getting enough air. I have an old Weber natural gas grill and I have had to clean the orifices several times over the years when the flame size dropped due to some oxidation and film from the stink chemical. You will need small numbered drill bits to clean them out. Be very gentle and be careful to get the right bit or you may damage the orifice or make it too large. Use the tiny bits by hand, not in a drill.

 

[Demosthenes9]

Natural gas grills don't use a regulator like LP models do. The gas pressure is regulated at the utility meter. That said it could be a low pressure issue with your meter pressure regulator. Your utility company can check it out for you. It should be around 7 water column inches. If you are getting a mostly blue flame it's not likely an issue with the burner tubes being restricted. The flame would be yellow if it was not getting enough air. I have an old Weber natural gas grill and I have had to clean the orifices several times over the years when the flame size dropped due to some oxidation and film from the stink chemical. You will need small numbered drill bits to clean them out. Be very gentle and be careful to get the right bit or you may damage the orifice or make it too large. Use the tiny bits by hand, not in a drill.

Just an FYI, but some Weber NG grills did ship with an inline regulator. I've dealt with a few of them. That said, the Genny 1000 didn't have one.

 

[Big George's BBQ]

You need to change the orifices specific to natural gas I am having to do this with my house as I am switching from propane to natural gas- heaters, stove and hot water heater

 

[jpbsarris]

Thanks Demosthenes9 for the info on Weber putting inline regulators on some of their natural gas models. I checked with Weber and they state that all their natural gas models are still designed to run off of 7 water column inches of pressure. They put regulators on some models for safety in case of an over pressure due to a faulty meter regulator but the inline regulators are still set at 7 inches.

 

[Demosthenes9]

Thanks Demosthenes9 for the info on Weber putting inline regulators on some of their natural gas models. I checked with Weber and they state that all their natural gas models are still designed to run off of 7 water column inches of pressure. They put regulators on some models for safety in case of an over pressure due to a faulty meter regulator but the inline regulators are still set at 7 inches.

Good to know. Thanks !