Compare tool
Compare models side by side
Pick two to four models. The best figure in each row is marked, and every number comes from the maker, NEEP or ENERGY STAR. Copy the URL to share a comparison.
All mini-splits & heat pumps ranked →All dehumidifiers ranked →All window, wall & room units ranked →All heating ranked →All parts, tools & supplies ranked →
| Spec | Mr. Heater Big Maxx MHU50 50,000 BTU Unit Heater (NG, LP kit included) | Heatstar 18,000 BTU Vent-Free Radiant Propane Heater with Thermostat and Blower |
|---|---|---|
| Photo |  |  |
| Our score | SCORE7.3 / 10 | Not reviewed yet |
| Our take | The garage heater we'd hang where there's gas: 40,000 BTU/h of vented, thermostat-controlled heat for a two- or three-car garage. Budget for a professional gas, vent and electrical install, and expect to clean the flame sensor. | 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. |
| Type | Vented gas unit heater | Vent-free propane |
| Max heat output | 40,000 BTU/h | 18,000 BTU/h |
| Fuel / power | Natural gas or propane | Propane |
| Indoor use per manual | Vented; qualified installer; 8 ft above a garage floor | n/a |
| Thermostat | Yes | Yes |
| Warranty | 3 yr | n/a |
| Watch out for | Installation and service by a qualified installer, service agency or the gas supplier, per the manual. Thermostat sold separately; propane needs an 11-14 in WC regulator (not supplied). Never in spaces with gasoline, solvents, paint thinner or airborne dust. | 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. |
| More | Model detailsOur full reviewView on Amazon → | Model detailsView on Amazon → |