You state it is on low burner. That could be taken as the flame is always low, which could be a low gas supply pressure, a restricted pipe or strayed gas regulator, among other problems.
The question would be if you have the pressure instruments a tech would have to examine the pressure and how to use them.
http://www.heatpro.us energy businessmen’s knowledge
Yes, you really have to find out the MAKE and MODEL to get good answers. There IS more than one machine made.
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