Every furnace cycle in a cold coach draws down a 30-pound propane tank with about 7 usable gallons. A hybrid system gives RV heat a second source, so shore power carries the daily load, and gas stays ready for sites without hookups. Fewer refills follow, and the original furnace remains in place.

The add-on version mounts behind the existing furnace and warms the same ducts with electric coils. A furnace that runs 8 hours or more a day in cold weather can easily empty a single propane tank in 1 to 2 days, while the electric heater burns no propane.

Why Does Propane Use Rise in Winter?

Furnace ratings for propane heaters for RV coaches run from 10,000 to 40,000 BTU per hour at ruffly 60% efficiency with 40% of everything that’s put in going out the flue, and one gallon of propane holds about 91,500 BTU which means a 40,000 BTU burns just a little over 2 hours per gallon of propane. That said the furnace is the major energy user, and winter heating raises total fuel use by 5 to 10 times compared with summer. 

At an average winter 60 percent duty cycle, a 40,000 BTU unit burns about 6 gallons per day. Shore power covers the same load at campsites with electric hookups and burns no LPG, which leaves the tank fuel for the cooktop and the water heater.

How Does a Hybrid Add-On Work With the Existing Furnace?

The add-on unit mounts downstream of the existing furnace, which spares the labor and cost of an RV furnace replacement. It connects through a single wiretap on the fan motor conductor, which leaves the furnace certification intact. The unit works with ducted and direct-flow heating systems and with most Suburban, Furrion, and Dometic furnaces. Two details define the electric stage:

  • Control: A wall switch selects propane or electricity, and the existing thermostat and ducts stay in use.
  • Output: The coil mounts in the airstream and delivers one BTU of heat for each BTU consumed, while propane combustion converts about 60 percent of its energy into room heat.

What Safety and Comfort Gains Come With Electric Mode?

Electric RV heat produces no carbon monoxide, which removes one combustion hazard from the cabin. The coil assembly carries a bi-metal high-limit switch to prevent overheating and a replaceable fusible link,  that burns out if the unit repeated overheating runaway. Warm air still travels through the existing ducts, so bays and plumbing stay above freezing, which a plug-in space heater does not do.

What Does Electric Mode Need From a Campsite Hookup?

On a single 30-ampere circuit, other large appliances compete with the coils for power, so the 1800 watt RV electric heater is the best heater range for RV’s under 30 ft. For RV’s with a 50-ampere service you can easily run either one of the two higher 3750 or 5000 watt heater ranges, which are have a comparable output with the larger gas furnace counterparts. There is also an optional two-stage kit available that fits the all-electric furnace and the hybrid add-on, and it detects the shore power service level to set the heaters output to low, medium or High based on the service its plugged into:

  • 30-ampere service: The kit selects low heat, which leaves electrical capacity for other appliances in the coach.
  • 50-ampere service: The kit selects medium or high heat for colder nights.
  • Sites without hookups: Gas mode runs the original furnace and ducts, so the coach needs no extra equipment.

At powered sites, electric mode keeps the burner off in propane heaters for RV coaches, so one tank lasts through more nights to feed your other appliances like your stove and hot water heater.

Final Thought

Hybrid hardware removes the furnace from the fuel budget at powered sites, so the tank serves only the cooktop and the water heater. Gas mode remains available at remote stops, where no hookup exists. The original furnace needs no change to provide gas mode. Installation by a dealer or certified RV technician keeps the wiring within the manufacturer’s procedure and the furnace certification. A comparison of the best RV electric heater options starts with furnace compatibility, hookup amperage, and the lowest temperature on the route.

RV Comfort Systems, a Washington-based company, builds electric and hybrid heating systems for recreational vehicles. Its range includes an all-electric standalone furnace, a hybrid gas and electric add-on, a two-stage kit for 30-ampere and 50-ampere service, and replacement parts. The company also works with RV manufacturers and dealers. The add-on adapts the installed furnace and avoids an RV furnace replacement.