Mr. Heater Big Maxx

Mr. Heater Big Maxx

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  • Heats up to 2,667 sq ft
  • 80,000 BTU output
  • Includes propane conversion kit
  • Must be mounted 8+ feet off the ground
  • Powered exhaust for vertical or horizontal venting
  • Spark ignition

Pros & Cons

What we like ...
  • 2,667 sq ft heating range
  • Conversion kit for propane included
  • Options for vertical or horizontal venting
  • Temperature control
  • High temperature safety shut-off
What needs improvement ...
  • Thermostat, hose, and regulator not included in base price
  • Requires clearance of 8+ feet from the ground

Product Summary

Mr. Heater Big Maxx is a permanent solution for your heating needs. The unit is powered by natural gas (with a propane conversion kit included) with enough output to heat up to 2,667 square feet. 

The heater requires ceiling installation with no less than 8 feet of clearance from the floor. Angled brackets for ceiling mounting are included as well as options for vertical or horizontal exhaust. 

This unit comes with a three-year warranty for heater parts, as well as a 10-year warranty on the heat exchanger. Overall this is a great option for turning your barn, garage, or shed into a workable space year-round.





29.33”L x 15.50”W x 26.37”H

Heating Coverage:

2,667 sq ft

Power Source:

Gas Powered


3 years on heater parts, 10 years on heat exchanger

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Mr. Heater Big Maxx

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      The Mr. Heater Big Maxx is an outstanding solution for permanently heating your barn, garage, or shed to use the space year-round. Once installed, this gas-powered heater provides more than enough output to heat your space for years to come.