Try going to www.boschhotwater.com/parts, and enter your model number. If a kit is available, they should be able to help you purchase one. If a kit is'nt available, you can drill the present burner orifice to twice the size of the hole you have now. You'll need to install a gas pressure regulator that's rated for natural gas use. It does'nt need to be a Bosch brand, just one the threads onto the gas supply pipe you use for the natural gas
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