Swap Genesis Silver A Manifolds


 

Dave-MI

New member
I have a Genesis Silver A that is propane, I want to switch it over to NG. If anyone here is looking to do the opposite, hit me up.

Here it is currently in disassembly:

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Be aware it's not possible to simply swap an orifice and have it operate correctly and most important SAFELY
I read up on that, but I don't see any real safety issues. We've got NG running at about 1/2 psi here, flowing through a hole into a tube with lots of holes in it. It isn't rocket science. If you asked me, I'd say Weber probably got out of supplying conversions because of our crazed litigious safety society.

I ordered a conversion kit last year that I just got around to installing. It did not come with the correct orifices, so I was stuck. My grill uses 1/8 NPT orifices, and all of these kits come with M6 threaded. I found a guy on ebay that makes orifices. He advised me to run 1.7mm orifices to get 13,000 BTU each. The standard setup on propane is 12,000 BTU per tube, so I'm pretty close.
 
Trust me as someone who was trained a bit by a licensed gas fitter. If you're trying to get an LP version of an early Weber Genesis product to run SAFELY and correctly on NG you CANNOT achieve it with orifices alone and anyone who tells you that you can is full of :poop: and lying to you. At issue is the actual valves NOT the orifices. I've written on these forums extensively about this and others here will vouch for the accuracy of what I am telling you. If you try to run your "converted SIC" grill on low even medium sometimes the flames will either go out or partially go out. Meantime this is happening in a closed space, and possibly with a hint of flame at one end of one of the burners. So now raw gas is building up in the closed space, and can cause a HUGE flashover (trust me on this point as I've seen it happen) and can damage the grill or worse yet you or anyone using the grill.
If you're going the other way (NG to LP) it's only a minor inconvenience as you will not be able to throttle the burners down to a "normal" low or medium setting. So YES IT IS ROCKET SCIENCE!!!!!!!!!!
Weber spec'd entirely different valves NOT just simple orifices.
Now how can you do it safely? Actually it's quite easy. The valves from a 2nd generation Genesis i.e. a Genesis B or C are the same valves. Simply acquire an ACTUAL NG model manifold from one of those. Many members here will help you find one. Actually a pretty friendly and helpful group.
Unscrew the entire valve from the manifold(s) and simply (with proper gas compatible pipe dope on the threads), screw the NG valves onto your manifold. Voila' you have a proper NG conversion not some hill billy YouTuber mock up.
And fwiw you DO NOT have 1/2 PSI gas at the gas line. If you do something is very wrong. PROPER gas pressure at the outlet should be 7"WC (7 inches water column) which is just about .25 PSIG
Now to that end I have seen some houses (only in Minnesota) where for whatever reason the builder and the gas company plumbed gas in at higher pressures than I've ever seen (though I did not measure them) and the houses were plumbed with small diameter flexible copper lines to each appliance with an add on regulator prior to each appliance to bring the pressures to the norm the appliance (furnace, gas water heaters, ranges etc) they were designed to operate at.
You will know if your house is like this by looking at the plumbing. If it's large diameter black pipe than it should NOT be at .5 PSI as that is twice the limit.
Now I'm not being a jerk here, and you can ignore good advice. If you do it's on you.
 
@LMichaels - I was just spitballing about the psi. Just making the point that it's very low pressure.

The kit came with a regulator as well, so my changeover wasn't just orifices. But you're saying the valves under the on/off/temp knobs are different for a NG Weber than a propane model, and it will be prone to flaming out at lower settings. I see where that could be an issue.

Is the only way for me to get proper valves to find some from an old Weber?
 
@LMichaels - I was just spitballing about the psi. Just making the point that it's very low pressure.

The kit came with a regulator as well, so my changeover wasn't just orifices. But you're saying the valves under the on/off/temp knobs are different for a NG Weber than a propane model, and it will be prone to flaming out at lower settings. I see where that could be an issue.

Is the only way for me to get proper valves to find some from an old Weber?
Yes exactly. And then another thing to be aware of when you find those old valves they're not set up for use with a NG regulator. They're set up to run at 7"WC (or "normal" NG line pressure). You can use the regulator but you would need ever so slightly larger orifices. Everything else will work well. A regulator CAN be beneficial on the Genesis but is certainly not necessary. One case you may want to use it in is if your grill supply is on the end of a very long supply or feed line with say other heavy use appliances on that line, water heater (especially a tankless on demand type), gas dryer, etc which all have a heavy draw down of gas and could cause bad fluctuations further down the line. Gas is nothing to be taken lightly. Even using something as innocuous as the wrong thread sealant can cause very bad problems. Which is why I come off a bit strongly as I see people taking this stuff and operation of gas appliances FAR too lightly and too many shysters on the web or YouTube telling you "yeah just buy our kit and all is well". It's not.
Now to be sure there are SOME Weber grills that you can get away with simple orifice swaps. I've only seen it on some (not all) Summit models. The thing is if you use these "kits" and something goes wrong, who is gonna stand behind the damages or injuries at worst or the inconvenience at best?
Bottom line finding an old (just be sure it was actually the proper fuel type) Genesis for free or very cheap is pretty easy. The valves simply unscrew. A little proper pipe dope on the threads and bam you're in business, fast, easy and most importantly SAFELY
 

 

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