PDA

View Full Version : Converting a propane grill to natural gas - have a few questions



Zero102
06-16-2018, 09:57 PM
I have a Master Forge MFA480BSP grill that I would like to convert from propane to natural gas. We bought this thing in Calgary where propane is cheap (thanks costco!) and moved to BC where it is costing me $30 to fill my 20lb tank. I know it's not a nice or a fancy grill but I already own it and since it's still in good shape I'd rather spend a few bucks converting it than several hundred replacing it.

I checked with Master Forge and they are basically a dead company and won't answer. Dyna-Glo makes an IDENTICAL grill with the part number DGA480BSP from which all of the parts interchange but they refuse to sell conversion kits.

I read up on how to convert grills and I think I have most of it figured out but I've got a couple questions I was hoping some of the old-timers or experts on here could help with. For the gas line I will be pulling a permit.

1) Since I can't buy a conversion kit I am going to have to drill the orifices myself. Right now the main burners have a 1.00mm orifice and the side burner has a 0.98mm. Using a conversion chart it seems I need to drill the main burners to 1.37mm and the side burner to 1.35. Am I correct that I would be close enough if I just drilled them all to 1.37? Also, did I mess up the math somewhere?

In the conversion guide I found from Master Forge (before they died as a company) located here: http://pdf.lowes.com/installationguides/6938457600181_install.pdf
They mention it is necessary to adjust the air shutters. My burners are not adjustable. They look like this: https://www.grillspot.com/media/catalog/product/cache/8/image/9df78eab33525d08d6e5fb8d27136e95/1/5/15611_4.png
And they just have a little grate on the end to allow air in.

2) Should I try to rig up a hose clamp or something to obscure part of the area or just leave them how they are? Should I change the drill size to compensate for this? The natural gas models use exactly the same part number burner, though I assume they might make up for this with the valves.

3) In the guide for every conversion they also mention adjusting a small screw in the valve to make sure the low heat settings work properly. Inspecting my valves they don't match any of the ones in the guide and there is a screw on the front of them but it doesn't seem to go to anything. It has no sealant or o-rings on it and is just a tapered head phillips head screw. The ones top left / bottom right hold the valve together, the one closer to the middle I have no idea what it does. Is this step necessary for me?... how does it correct the low heat performance, and what can I do to make up for it if needed?
https://i.imgur.com/kGQwUHY.jpg

4) I hope this is an easy one - where the propane hose connects to the manifold there is a flare fitting that takes a ~3/4" wrench and has an opening inside the threaded area about 1/2". Is this a 3/8" flare fitting or a 1/2"? I can't find a good diagram with measurements for gas fittings.


Thanks in advance for any help!

interlude
06-20-2018, 11:10 AM
So apparently this is a bad idea.

Someone mentioned that if something were to happen (i.e. your house burned down due to a fire with your bbq) and they find out that it was converted and was the cause of a fire, then you will not be covered. If someone can confirm it would be awesome! As I want to convert my propane bbq to natural gas as well!