Dr. Infrared Heater DR-975 Garage Heater Review

Run the garage math on a bigger space and the DR-966 starts to look small. A three-car garage is 600–700 square feet; at the usual 10 watts per square foot for an insulated space, that's 6,000–7,000 watts just to hold a working temperature, with nothing left for a cold morning or a door that's been open. The DR-975's 7,500 watts is that margin. It's about 25,600 BTU — half again what a 5,000W Comfort Zone makes and 25% over the DR-966 — from the same kind of compact steel box on the same kind of wall-or-ceiling bracket. Low is 4,700 watts, which is enough to keep a big garage above freezing overnight without paying for high.

The upgrade most owners will notice day to day isn't the wattage, it's the remote. The DR-966's thermostat dial lives on the unit, which is fine once and annoying forever if the heater's on the ceiling; the DR-975 puts the 50–85°F thermostat and a timer on a handheld remote, and Dr. Infrared sells an optional wall thermostat if you'd rather hardwire one. The elements are spiral steel with a low sheath temperature, the motor is enclosed and thermally protected, and the whole unit is UL and cUL listed. It's louder than a living-room heater, as any unit heater is, and the five louvers let you aim it down across the floor.

The catch is the circuit. At 7,500 watts on 240V the heater draws over 31 amps, so it needs a dedicated 40A breaker and 8 AWG copper — not the 30A / 10 AWG run that serves the DR-966 and the 5,000W units. If you're already paying an electrician, the incremental cost is modest; if you have an existing 30A circuit, the DR-966 is the right heater and the DR-975 is the wrong one. Mount it to structure, keep solvents and sawdust away from the intake, and follow the manual's clearances. For a big or drafty shop that you want to heat with electricity, this is the one.