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SpecMr. Heater Big Buddy 18,000 BTU (MH18B, no fan)Heatstar 18,000 BTU Vent-Free Radiant Propane Heater with Thermostat and Blower
PhotoMr. Heater Big Buddy 18,000 BTU (MH18B, no fan)Heatstar 18,000 BTU Vent-Free Radiant Propane Heater with Thermostat and Blower
Our scoreSCORE7.0 / 10Not reviewed yet
Our takeA good heater for blinds, shelters, camp and outages on 1 lb cylinders, with a low-oxygen shutoff and tip-over switch. A closed garage isn't on its manual's indoor list, and there's no thermostat or fan.A fixed vent-free heater that adds the thermostat and blower the Big Buddy lacks, for a cabin you heat all winter. It's an installed heater, so its own manual sets the fuel supply, room size and venting rules.
TypePortable propaneVent-free propane
Max heat output18,000 BTU/h18,000 BTU/h
Fuel / powerPropanePropane
Indoor use per manualRecreational enclosures + emergency, 1 lb onlyn/a
ThermostatNoYes
Watch out forThe Massachusetts and Canada version (F274806) ships with a manual that says For Outdoor Use Only; check for F274805 before using it indoors. Not for use in a dwelling home in California, per the US manual. The low-oxygen shutoff does not detect carbon monoxide; run a battery CO alarm listed to UL 2034 wherever the heater runs. Using third-party attachments or cooking on it voids the warranty.We haven't read this heater's manual; check its room-size and ventilation limits before you buy. Never run an unvented fuel-burning heater in a room where people sleep (CPSC). The low-oxygen shutoff does not detect carbon monoxide; run a battery CO alarm listed to UL 2034 wherever the heater runs.
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