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How Does An RV Furnace Work? – Important Things to Know

Written by Philip Lopez / Fact checked by Paul Lemaire

how does an rv furnace work

RVing is almost impossible to do in winter with all the ice and chilly weather. The good news is that you can still go ahead with your RV camping trip in the middle of winter as long as you have an RV furnace.

But how does an RV furnace work exactly?

Generally, an RV furnace is fueled by both propane and electricity to circulate the heat inside your RV. Also, that depends on what type of RV furnace you have – forced air, vent-free, or electric. Let me discuss the mechanism in detail below.

Table of Contents

The Basic Mechanism Of RV Forced Air Furnaces

Probably, the most common type of RV furnaces is the forced propane model. This type consists of basic components, such as a thermostat, blower motor, and circuit board. There are also vents for air intake, exhaust, and a safety limit switch.

How this works is simple. The blower motor gets activated when the thermostat reaches a higher heating temperature than your camper trailer. The heater then initiates to circulate warm air through the ducts until the desired temperature is achieved around your RV.

The forced air propane furnace needs both propane and electricity to work. Propane burns to produce warm air, while electricity powers the blower motor and the fans for heat circulation.

Many RVers love this model because it’s durable and easy to repair. Since it warms the basement along with the RV cabin, it prevents freezing of the RV pipes. On the downside, this model can be a bit noisy and costly as it uses a lot of propane and electricity.

Alternatives To Forced Air Furnace


If you don’t like the noisy operation of an RV forced air furnace, you can pick between these two alternatives.

  • Vent-Free Propane Heater

The vent-free propane heater looks like a standard home heater, but it works solely on propane. This unit is a more efficient and quieter alternative to a forced air furnace because it consumes less propane, hence saving on electricity costs. It’s available in various sizes, ranging between 5,000 BTUs and 30,000 BTUs.

For safe operation, you’ll need this unit vented while running. You can keep one window slightly open for proper ventilation. The only danger it poses is the potential buildup of carbon monoxide when you use the unit in a smaller RV as it accumulates a large amount of moisture.

The good news is that those vent-free heaters made in the United States integrate an internal oxygen sensor to automatically turn off the unit if oxygen levels get dwindled in the room. This safety feature, along with an LP detector, makes this unit a practical option for RV use.

  • Electric Heat Pump Air Conditioner (AC)

An electrical heat pump AC can also function in reverse to offer heat. During hot days, the heat pump releases hot air outside. Conversely, the unit removes heat from the air outside and moves it inside the rig during the cold weather.

The main benefit of a heat pump AC is its ultra-quiet operation. This unit only consumes electricity and is very safe to use. However, this type may drain your batteries fast when you connect the AC unit to shore power.

RV Propane Furnaces Vs. Electric: What’s Better

Determining which is better between propane and electric furnaces depends on your camping style. If you seldom camp in cold weather, you’re better with a built-in RV propane heater to keep your pipes and yourself warm effortlessly. The expense of propane won’t be not that much since you’ll only camp once in a while.

When you find yourself camping in temperatures below 40 degrees Fahrenheit often, you might want to look for extra heating options if all you have is a heat pump. The heat pump might be enough if you never camp in very cold temperatures.

An electric furnace might also be ideal if you camp in a place where electricity is part of the fees. It’s also a better option if propane is difficult to come by in your camping area or propane is significantly expensive.

If you’re a boondocker, propane-fueled furnaces might be your best option. Using an electric model means running a generator, which is bad to run all night. To save battery power, consider getting a portable propane heater.

How Long Will RV Furnaces Operate On Propane


In general, a gallon of propane can last for around 95 hours, provided that it burns at a rate of 1000 BTUs. With a 30,000 BTU furnace, you can expect the furnace to consume the entire tank in 3.17 hours.

Now, there are several factors that might affect the calculation of propane furnace usage. Such factors include the size of the tank and the furnace’s BTU rating. For RVs, the common tank size is about 20 lbs. Typically, a 20-lb tank contains 4.5 gallons of propane.

Keep in mind that larger furnaces will consume more fuel. To extend the life of your RV propane, consider installing an RV skirt to keep the underside of your rig warmer in cold weather.

Will The RV Furnace Work Without A Battery

Without a robust 12-volt DC house battery power source, your furnace won’t offer the heat you desired. The RV furnace’s blower fan works on batteries, while heat is actually generated from propane. Most of the furnaces consume eight amps of power.

The furnace will work without being connected to electricity as long as you have adequate battery power. Suppose you have two 12-volt, 100-amp batteries offering 200 amp-hours. You shouldn’t drain it down to more than 50% of its capacity.

If your batteries only power your heater, you can expect it to run nonstop for about 12.5 hours (given that a blower fan uses 8 amp hours).

Safety And Maintenance Tips

  • Check all the ducts and ensure that they’re correctly connected to their corresponding registers. Make sure that the ducts are clean.
  • Test the regulator, delivery line pressure, as well as propane piping system for leaks at least once for every camping season.
  • Consider installing fire extinguishers and carbon monoxide detectors to detect fire hazards.
  • While visual inspection is good, it’s also a wise choice to let your RV furnace be professionally serviced once a year.


I hope this article has shed light on your question “how does an RV furnace work?”. Fundamentally, RV furnaces use propane, electricity, or both in powering their heating functions. Like with all other appliances, check the RV furnaces regularly to ensure their safety and efficiency.

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