I need to change over a ten year old Intertherm from LP gas to Natural Gas.
Is this a matter if changing the Orifaces on the burners similar to a gas cookstove? The regulator simply has to reverse the oriface within it but I am having difficulty locating the orifaces for the burners.
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Most moble home/Intertherm, I'm guessing. The orifice screws right into the gas valve.

Do not forget to change the pilot oriface if it has one.

RE: Intertherm

I am in an area where no one will service this unit.
I have found on the furnace the instructions for the regulator(pilot light) change is done by removing and reversing the oriface within the regulator. I have been unable to locate orifaces for the burners if they take them. I have tried numerous repair shops in Kansas City to no avail.
Thank You for your input.
Joe G.

RE: Intertherm

I am in an area where no one will service this unit.
I have found on the furnace the instructions for the regulator(pilot light) change is done by removing and reversing the oriface within the regulator. I have been unable to locate orifaces for the burners if they take them. I have tried numerous repair shops in Kansas City to no avail.
Thank You for your input.
Joe G.


I hate to tell you this but setting up or changing a burner from LP to natural gas is more involved that just changing the or reversing the valve regulator.

Usually in this order

Gas off
Remove burner
Replace LP with natural gas orifice
Replace pilot orifice LP to natural (sometimes there is NO pilot orifice)
Replace thermocouple if equiptment (easier to do when burner out)
Obtain manometer and attach
Take reading at valve to see if within 3.0 to 3.5 inches water for natural gas
Light pilot and check for flame strength and adjust thermocouple if necessary
Open main gas and check for proper operation.

Caution. All Mobile home units have a built in combustion air system. Make sure it is functioning properly.


BTW What is the exact name and model number on the unit. I will see if I can locate the orifices in my book.

HVAC1000,
Greatly appreciate your advise on this matter. I have spoke with an hvac repairman that did not want to try and locate the parts. He will come by and check the furnace after I have obtained the orifaces.
Intertherm Model # MGBB-070 ABFC-01
Serial # MGB 9505-05700
Main Oriface is 23
Output BTU 57,000

HVAC1000,
Greatly appreciate your advise on this matter. I have spoke with an hvac repairman that did not want to try and locate the parts. He will come by and check the furnace after i have obtained the orifaces.
Intertherm Model # MGBB-070 ABFC-01
Serial # MGB 9505-05700
Main Oriface is 23
Output BTU 57,000


PILOT ASSY(.014 PILOT ORIFICE) Part number 660869

689009 GASKET,BURNER

902901 BURNER ASSY MHGA

They do not show a burner orifice just a burner with orifice.
A nautral gas orifice will be larger than a propane one. If we can find the size it can be drilled out with the proper size drill bit.

http://www.qualityhtg.com/pdf/mg-mm_downflow.pdf


Quality Heating and Cooling Supply - Inteftherm Parts Search Page (http://www.qualityhtg.com/q2/interthermsearchresults.asp?page_guid=%7B46210AC0% 2D47A5%2D45E5%2DBD8A%2DF0FC0475458D%7D)