Heating an RV, Garage or Workshop

RV shore power: know your amp budget first

Before you plug anything in, know whether your site gives you a 30 amp or 50 amp hookup. A 30 amp connection at 120 volts gives you a ceiling of about 3,600 watts total for the entire RV — air conditioner, microwave, water heater, and everything else combined. A 1,500 watt heater alone draws roughly 12.5 amps, which is a significant slice of that budget. A 50 amp hookup (typically split across two 120V legs) gives far more headroom and is usually enough to run a heater alongside an air conditioner or microwave without issue.

Worked example: 30 amp site running a heater and an AC unit

Say your rooftop air conditioner draws about 13 amps on startup and 10 amps running, and you add a 1,500 watt heater at 12.5 amps. That's roughly 22.5 amps continuous — comfortably under 30, until the fridge, converter charger and a microwave cycle on at the same time and push you over. The practical fix is simple: run the heater on its lower wattage setting, or run it instead of the AC rather than alongside it, and use the timer so it isn't drawing power while you sleep with everything else also running.

Amp draw vs available circuit capacity

These figures are illustrative starting points, not a substitute for checking your actual panel and RV documentation — see our full safety guidance for circuit and outlet practices.

RVs and campers in practice

An RV interior is small, which works in your favor, but thin-walled, which does not. On shore power, a compact electric ceramic heater is a popular alternative to running the propane furnace: it's quiet, dry, and doesn't consume fuel you have to refill. Expect it to hold a comfortable temperature in mild-to-moderate cold, and to struggle below freezing without help from the furnace or additional insulation (window covers, skirting).

• Check your site's amperage before running the heater with the AC or microwave
• Keep it on the floor on a flat, stable surface, away from curtains, bedding and upholstery
• Use the timer overnight rather than continuous unattended running
• Crack a roof vent or window — sealed RVs build condensation fast in cold weather

Recommended in this guide

The compact heater this guide keeps coming back to

RapidHeat is a portable ceramic fan heater for personal and supplemental room heating. Room results depend on insulation, drafts, ceiling height and starting temperature; it is not a whole-home heating replacement.

• Ceramic fan heating
• Remote control included
• Programmable timer

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Garages: insulation is the real variable

The single biggest factor is insulation, not the heater. An insulated, sealed single-car garage can be brought to working comfort by a compact heater aimed at the bench area. An uninsulated garage with a bare metal door loses heat as quickly as you add it, and no plug-in unit will win that fight — see our broader notes on heating larger or leaky spaces.

• Insulate the garage door first — it's the single biggest leak and cheapest fix
• Seal the gap under the door with a weather strip
• Heat the zone you actually work in, not the whole garage volume
• Never run a heater near gasoline, solvents, paint or the car's fuel filler

Condensation and moisture

Electric ceramic heat doesn't add moisture the way an unvented propane heater does, but sealed spaces — RVs especially — already trap humidity from cooking, breathing and showers. Warm air holds more moisture, and when it meets a cold window or metal surface, it condenses. Crack a vent slightly when running a heater in a closed-up RV or garage overnight to let that moisture escape rather than pool.

Fuel and chemical safety warnings

• Never place a heater within three feet of gasoline, propane tanks, or fuel cans
• Keep it away from solvents, paint, aerosols and rags used for staining or cleaning
• Sweep sawdust and shavings away from the heater's intake and outlet before switching on
• Do not run any electric heater in a fully sealed, unventilated space overnight

What to expect, and what not to expect

Physics doesn't care about marketing: a 1,500 watt heater in a leaky, uninsulated bay will make the air you're standing in tolerable, and nothing more.

Where RapidHeat fits

RapidHeat is intended for portable supplemental heating. Before RV, workshop or garage use, confirm the electrical rating, ventilation, prohibited locations and safety features in the supplied instructions; never use it near fuel, solvents or sawdust. See sizing advice or check bundle pricing.

Common questions