RV Air Conditioning: Know Your System Before You Fix It
Your RV air conditioner isn't the same as a house AC. Understanding what type you have, how it works, and what to look for saves you time, money, and frustration.
Not All RV Air Conditioners Are the Same
You know something isn't right with your AC, but when you start looking for answers you hit a wall of generic advice that doesn't match what's actually on your RV. That's because RV air conditioning systems vary widely depending on your rig, its age, and how the manufacturer set it up.
Some RVs have a single rooftop unit blowing straight down into the room. Others have two or three units connected to ductwork running the full length of the ceiling. Some motorhomes tuck the AC underneath in a basement bay. And now, newer units include heat pump capability that changes how the whole system works in cooler weather.
Understanding what you have is the first step toward getting it working the way it should. Here's what you need to know.
Types of RV Air Conditioners
RV air conditioners come in three main configurations. The type you have determines how it's serviced, what parts it needs, and what problems to watch for.
Rooftop Air Conditioners
The most common type on travel trailers, fifth wheels, campers, and motorhomes. Rooftop units mount over a standard 14"x14" ceiling opening and sit on the roof under a plastic shroud. They're exposed to sun, rain, road vibration, and debris year-round.
Most RVs have at least one rooftop unit. Larger rigs often have two or three. These can be ducted (air distributed through ceiling vents) or non-ducted (air blows directly from the ceiling assembly).
Common brands: Dometic, Coleman-Mach, Advent Air, Furrion Chill, GE
Rooftop AC Service →Basement Air Conditioners
Found on some Class A motorhomes and higher-end fifth wheels, basement units are mounted underneath the RV in an enclosed storage bay. They cool through a ducted system that runs up into the living space.
Basement AC systems are quieter in the living area and don't add height to the roof profile. However, they require proper ducting, insulation, and airflow management to work efficiently. Access for service is different than rooftop units.
Common brands: Coleman, Dometic, GE, Furrion
Basement AC Service →Underbunk & Wall-Mount Units
Some RVs mount the air conditioner under a bunk, bed platform, or on a wall similar to a window-style unit. These save roof space and reduce wind noise while traveling, but they still have the same core components as rooftop models.
Wall-mount and window-style units are most common on smaller RVs, pop-ups, and truck campers where roof mounting isn't practical. They require adequate airflow clearance and proper electrical supply to operate correctly.
Common in: Smaller travel trailers, pop-ups, truck campers, Class B vans
Underbunk AC Service →Ducted vs. Non-Ducted: How Air Gets to You
Regardless of where the AC unit sits, the air it produces reaches you in one of two ways. This matters for performance, comfort, and diagnosing problems.
Ducted Systems
A ducted AC pushes cooled air through ductwork built into the ceiling and distributes it through vents placed throughout the RV. A wall-mounted thermostat generally (but not always) indicates a ducted system.
Advantage: Even cooling throughout the entire RV. No hot spots. This is the most effective way to circulate all the air in the living space.
The catch: Ductwork must be properly sealed. Any air leak is a detriment to the system. Leaky ducts blow cold air into the attic space or pull hot attic air into the return, causing poor cooling and premature unit failure. This is one of the most common problems we diagnose.
Non-Ducted (Free-Blow)
A non-ducted AC blows cooled air directly from the ceiling assembly into the room below it. Controls are on the unit itself rather than a wall thermostat. Sometimes called "free-blow" units.
Advantage: Simpler system with fewer parts to fail. No ductwork to seal or maintain. Easier and faster to install or replace.
The catch: Cooling is concentrated near the unit. Areas farther from the AC get less airflow. In longer RVs, a single non-ducted unit may not cool the bedroom or rear section effectively.
Bolt-Down Style Units: Some RVs use a bolt-down interior assembly that sits flush with the ceiling instead of the traditional square box that hangs down with a visible filter. These are generally quieter, but the ductwork connections behind them are seldom sealed properly from the factory. Unsealed intake or output ducts cause cross-flow between supply and return air, which leads to poor cooling and puts unnecessary strain on the compressor.
Heat Pump AC Units: Cooling and Heating in One
Some RV air conditioners include a heat pump, which means the same unit can both cool your RV in summer and heat it in cooler weather. This is becoming more common on newer RVs and aftermarket replacement units.
How a Heat Pump Works
A standard AC removes heat from inside your RV and releases it outside. A heat pump does the same thing but can also reverse the process: it extracts warmth from the outdoor air and moves it inside. It's the same refrigeration cycle running in reverse.
This means one unit handles both jobs. In cooling mode, it works exactly like a regular air conditioner. In heating mode, it provides electric heat without propane. Heat pumps use significantly less electricity than a resistance heater (electric strip heat), making them more efficient when connected to shore power.
When a Heat Pump Makes Sense
You camp in mild to moderately cool weather (above freezing) and want to avoid running the propane furnace.
You have reliable shore power at campgrounds and want to reduce propane costs.
You're replacing a rooftop unit anyway and want the added capability for little extra cost.
What a Heat Pump Won't Do
It won't replace your propane furnace in freezing conditions. Most heat pumps lose effectiveness below about 40°F and stop working entirely around 20°F.
Some units include an electric resistance backup strip for colder temps, but these draw heavy amperage and are only practical on shore power.
A heat pump is a complement to your furnace, not a replacement for it.
Heat Pump vs. Electric Strip Heat
Some older AC units offer "heat" capability through an electric resistance strip, which is essentially a space heater built into the air handler. This works but uses substantially more electricity than a heat pump to produce the same amount of heat. If you're comparing units, a true heat pump is more efficient than strip heat in every scenario where the outdoor temperature is above its operating minimum.
What About a Mini Split?
If you've searched for quieter AC options, you've probably seen people suggest a residential mini split. And if your RV is permanently parked, that can be a viable option. Mini splits are quieter, more efficient, and provide excellent climate control.
But if your RV travels, a mini split is not the right choice. These systems are not built for the vibrations, road shock, and constant movement that comes with towing or driving an RV. The refrigerant connections, mounting points, and line sets will eventually fail from the stress. It's not a question of if, it's when.
If noise is your primary concern, there are better solutions. Newer RV-specific units from Coleman-Mach, Furrion, and others have reduced noise levels significantly. Proper duct sealing, vibration dampeners, and the bolt-down style interior assemblies all reduce operating noise while keeping a system that's actually designed for life on the road.
Major RV Air Conditioner Brands
We service all major RV AC brands. Each manufacturer has different design approaches, common failure points, and parts availability. We know the differences.
Is Your RV AC Working Properly? A Quick Check
Manufacturers recommend this simple temperature split test. With the unit running on high fan (or high fan auto) and the thermostat set well below room temperature, let it run for 15 minutes. Then:
Step 1: Place a thermometer in the air intake (where the unit pulls air in) and record the temperature.
Step 2: Place the same thermometer at the closest output vent to the AC unit and record that temperature.
Step 3: Calculate the difference. If the split is 16°F or more, the AC unit itself is doing all it can.
If the unit passes this test but your RV still isn't cool enough, the problem isn't the air conditioner — it's somewhere else in the system. Ductwork leaks, poor insulation, or other issues that require a full diagnostic to identify. That's where we come in →
Maintenance That Keeps Your AC Running
Manufacturers recommend the following to get the most life and best performance from your RV air conditioner:
Every week during use: Clean or rinse the filter. A dirty filter is the single easiest thing to fix and the most commonly overlooked.
At least once per year: Full professional cleaning and service of the coils, drain pan, electrical connections, and mechanical components.
Twice per year in dusty conditions: If you camp near dirt tracks, construction areas, or desert environments, the extra dust buildup in the coils warrants a second service.
Seal all ductwork: Any air loss in the duct system reduces cooling output and makes the unit work harder than it needs to. Proper sealing is not optional — it's essential.
RV Air Conditioning Service Pages
Find the information specific to your system, or call us and we'll point you in the right direction.
RV AC Repair & Service
Common problems, repair vs. replace guidance, and diagnosis for all RV air conditioning systems.
Rooftop AC Repair
Service and repair for roof-mounted units — the most common RV AC configuration.
Basement AC Repair
Diagnosis and service for basement-mounted AC systems on motorhomes and higher-end fifth wheels.
Underbunk & Wall-Mount AC
Service for underbunk, wall-mounted, and window-style units used in smaller RVs and campers.
RV Air Conditioning: Common Questions
RVs use three main types: rooftop units (the most common, mounted on the roof over a standard 14"x14" opening), basement units (mounted underneath in a storage bay, found on Class A motorhomes and some high-end fifth wheels), and underbunk or wall-mount units (mounted under a bed platform or on a wall, used in smaller RVs). Each type can be ducted or non-ducted, and some include heat pump capability for both cooling and heating.
A ducted AC pushes cooled air through ductwork and ceiling vents throughout the RV, typically controlled by a wall-mounted thermostat. A non-ducted unit (also called free-blow) blows air directly from the ceiling assembly into the room below it with controls on the unit itself. Ducted systems distribute air more evenly but require properly sealed ductwork to function correctly. Non-ducted systems are simpler but concentrate cooling in one area.
A heat pump is an AC unit that can also heat your RV by running its refrigeration cycle in reverse — extracting warmth from outdoor air and moving it inside. Heat pumps work well in mild to moderately cold temperatures and use less electricity than resistance (strip) heaters. They won't replace a propane furnace in freezing conditions, but they extend the usable temperature range of your AC into cooler weather without using propane.
Only if your RV stays in one place permanently. Mini split systems are not built for the vibrations and road shock of travel. The refrigerant connections and line sets will eventually fail from constant movement. For traveling RVs, a purpose-built rooftop, basement, or underbunk AC is the correct choice. If noise is the concern, there are quieter RV-specific units and noise-reduction options available.
Run the unit on high fan with the thermostat set well below room temp for 15 minutes. Measure the air temperature at the intake, then at the closest output vent. If the difference is 16°F or more, the AC unit is doing its job. If the RV still isn't cool enough, the problem is elsewhere — ductwork leaks, insulation issues, or other system problems that require professional diagnosis.
Questions About Your RV Air Conditioning System?
Whether you need a diagnosis, a repair, or just want to understand what you're dealing with — we're here to help.