Golf Simulator in a Cold Garage: A Colorado Winter Setup Guide (Temperature, Condensation, Power, Heat)
Garages are the most common place for a home sim and the hardest place to run one in winter. This guide is written for Colorado's Front Range, but the numbers apply anywhere it freezes.
How cold it gets, and what the gear is rated for
Denver's normal January high is 44–45°F and its normal low is 18–19°F (1991–2020 normals), with a January mean of 31.7°F (NWS Boulder). An unheated garage usually sits somewhere between outdoor and indoor temperature. Put a cheap thermometer out there for a week before you plan your sessions.
| Item | Published temperature rating |
|---|---|
| BenQ AK700ST projector | Operating 0–40°C (32–104°F) (BenQ) |
| Optoma ZW350ST projector | Operating 0–40°C, max humidity 80%, max altitude 2,500 m (Optoma) |
| Optoma GT2000HDR projector | Operating 0–40°C, max humidity 80%, max altitude 2,500 m (Optoma datasheet) |
| Garmin Approach R10 | Operating 14–131°F; charging only 32–113°F (Garmin) |
| Bushnell Launch Pro | No operating range found; Bushnell says store it in "a cool, dry environment" (Bushnell) |
| Impact screens and mats | No temperature ratings found on the maker pages we read. Ask the maker before leaving them in a freezing garage. |
What that means: on a normal January night a garage can be below every projector's 32°F floor. The fix is simple: heat the garage up before you turn things on. The Garmin R10 can run colder than the projectors, but it won't charge below freezing, so charge it indoors.
2,500 m is about 8,200 ft (our conversion). If you live above that, check your projector's manual for altitude guidance before buying.
Condensation: the cold-to-warm problem
Sony's projector manual describes the risk clearly: if room temperature changes rapidly, or a projector moves suddenly from a cold place to a warm one, condensation can form inside, and that "may cause malfunction." Sony's advice if it happens is to leave the projector on for about two hours before use (Sony help guide). That's one maker's manual, so check yours, but the physics is the same for any electronics.
- Warm the room slowly. Start the heater well before you plan to play, rather than blasting hot air at a freezing projector.
- Portable units come inside. The R10 and MLM2PRO are small enough to keep in the house and bring out once the garage is warm.
- Bringing gear in from the cold? Let it sit in its case and come up to room temperature before you power it on.
Power: what the sim draws
| Device | Published power |
|---|---|
| BenQ AK700ST | 212 W typical at 110V (BenQ) |
| Optoma GT2000HDR | 98 W min, 139 W max (Optoma) |
| Optoma ZW350ST | 98 W min, 139 W max (Optoma) |
| Gaming PC | Varies widely by build. Check the power supply rating and the graphics card maker's figures. |
A standard 15-amp, 120-volt circuit is 1,800 W at its breaker rating (15 x 120). For loads that run 3 hours or more, the common electrician's rule from the National Electrical Code is to stay at 80%, or about 1,440 W on that circuit (CalcMyPower explainer). A projector and PC fit easily. Add a 1,500 W plug-in space heater and you are over that line on a single 15-amp circuit. Put the heater on its own circuit, or move to a hardwired heater.
Heating the garage safely
Hardwired 240V garage heaters
Example: the Master MH-05-240-GH is a ceiling-mount electric garage heater rated 2,500/5,000 W (8,500/17,000 BTU), for areas up to 540 sq ft, on 240 V / 30 A. Master notes that the ceiling mount keeps it away from flammable fumes near the ground and that it needs no ventilation (Master/JJS Tech). A 240 V, 30 A circuit is a job for a licensed electrician, and you may need a permit.
Mount any heater where a mishit can't reach it, behind the golfer and out of the swing path.
Plug-in electric space heaters
The U.S. Consumer Product Safety Commission's 2026 winter guidance (CPSC):
- Keep portable heaters at least 3 ft away from drapes, furniture, bedding and other combustible materials. In a sim bay that includes the enclosure fabric and foam padding.
- Plug electric space heaters directly into a wall outlet, never into an extension cord or power strip.
- Turn heaters off when sleeping. In practice, don't leave one running in an empty garage.
Fuel-burning heaters and carbon monoxide
CPSC warns that fuel-burning heating can produce carbon monoxide, an odorless, colorless and deadly gas, and recommends CO alarms on every level of the home (CPSC). CPSC also says never to run a generator inside a home, basement, shed or garage (CPSC). For an attached garage sim, electric heat avoids the combustion question entirely.
Other garage details
- Garage door windows wash out the picture on sunny winter afternoons. The Indoor Golf Shop sells a blackout screen for the SIG10 "to help with screen washout in bright rooms" ($524.99 add-on) (SIG); Carl's DIY kit uses light-absorbing BlackStop fabric (Carl's).
- The door track sets your ceiling. See the ceiling guide.
- Altitude changes ball flight. Set your elevation in the launch monitor app; Rapsodo's rule of thumb is 3–5% more distance per 1,500 ft of elevation (Rapsodo).
Winter session checklist
- Heater on (its own circuit), with 3 ft of clearance.
- Wait until the bay is comfortably above freezing before powering the projector and PC.
- Bring the portable launch monitor out from the house.
- Close the door before you hit; check that the screen hangs freely.
- Afterward: heater off, launch monitor back inside to charge.