Heating, Air Conditioning, Fridge, HVAC/lennox unit heater


Good morning

 My question I hope is simple one.  I have an old lennox unit heater running on natural gas right now. I would like to move it to another building and run on propane. Can I

Lennox Unit Heater
mod. LF-120-M
Ser. 025109
Max input 120.000
Mas output 96.000
volt 115 cycle 60
6 burners with 44 size orfice
the only numbers I could find on the valve is ink stamp look that says 3.5 AG

Thank you and have a great day



You would need a propane conversion kit to run on propane ,which consists of a small spring that replaces the natural gas spring of that particular brand and model main gas valve and possible a small ball bearing and you would have to change the 6 burner brass orifices.A Lennox dealer/distributer typically do not sell  to DIYers . Briefly googled lennox propane conversion kits,looks like they make them for your model.  You would have to check and set the gas valve to aprox. 11" . natural gas is somewhere around 3.5"

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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