From model numbers to rooftop checks, this guide walks you through the process of how to identify—and understand—your current setup so you can confidently select a new A/C unit that’s not only a match on paper, but also a perfect fit for your camper.
Step 1: Confirm What You Have
To confirm what type of RV A/C unit you have, start by locating the model number on your existing unit. This is usually printed on a sticker or metal plate attached to the rooftop unit itself. The label typically includes the manufacturer’s name, model and serial numbers, and sometimes BTU and electrical specs.
There are a few ways to find this information, depending on your setup:
- From the roof: Climb on top of your RV and remove the A/C shroud. Look for the sticker on the top or side of the housing, near the rear of the unit. Dust and condensation can sometimes obscure these labels, so a flashlight and a cloth can help.
- From inside the coach: Remove the ceiling-mounted grille and air filter. Look underneath the base pan for a narrow label with the model and serial number.
We recommend starting inside the coach, since you’ll need to remove the air filter cover anyway to identify the part numbers for the control box or ceiling assembly. Snap a few photos with your phone for reference later. (You’ll thank yourself when you’re standing in the parts aisle—or on hold with tech support.)
If you have a ducted system, you'll also want to identify your wall thermostat model, which is often found on the back of the thermostat’s faceplate or mounting plate. Some systems, like Coleman-Mach, use an “RVP” code (rather than a part number) that’s specific to the RV industry.
While it’s always wise to save any owner’s manuals or installation manuals you receive when purchasing a camper, this documentation is often generic and covers a range of models. The specific model or series numbers for your A/C should be on the RV’s build sheet, but even if you have this paper, it's still smart to cross-check it with the A/C unit itself.
If you’re really stuck, consider reaching out to the manufacturer or dealer with your RV’s year, make, and model. They may be able to tell you what was originally installed.
Step 2: Find the Right Replacement
With the part numbers in hand, you’re ready to shop smart. The great news? You don’t have to stick with the same model or series. The better news? You might be able to upgrade without overhauling your entire system—as long as you check for a few key compatibility factors first.
Brand Compatibility and System Fit
While brand loyalty isn’t a must, it can definitely make your life easier. For instance, if you have a Coleman-Mach, Dometic, or Furrion unit, sticking with the same brand—or at least the same mounting and control system—can lead to a cleaner install with fewer wiring surprises.
That said, some aftermarket units are designed to be “drop-in” replacements for other brands, and come complete with adapter kits to help bridge any compatibility gaps. Just know that “drop-in” doesn’t always mean plug-and-play.
Ducted vs. Non-Ducted Configuration
Is your system ducted (where cool air flows through vents in the ceiling) or non-ducted (where the air blows directly into your living space from the unit)? This distinction is crucial.
Ducted systems usually depend on wall thermostats and internal air distribution boxes, while non-ducted units often feature manual controls right on the ceiling assembly. Switching between the two can mean new wiring, control panels, or even modifications to your ceiling, so it’s generally best to stick with your current configuration.
BTU Rating
A BTU rating—short for British Thermal Unit—is technically a measure of how much energy it takes to heat one pound of water by one degree Fahrenheit. But for this A/C shopping mission, all you really need to know is: more BTUs = more cooling power.
Most RVs use either 13,500 or 15,000 BTU rooftop units, with the latter providing a noticeable boost for larger rigs, sweltering climates, or areas with high humidity. There are also lower-BTU models available for vans, pop-ups, and compact trailers where space and electrical capacity are more limited.
But choosing the right BTU level isn’t just about square footage. Here’s what else you need to consider before you click “add to cart”:
- Ceiling Height: Taller ceilings create more air volume to cool. If your RV has a high interior clearance, you might need a higher-BTU unit to maintain a comfortable temperature on hot days.
- Number of Windows: More windows—or large, sun-facing ones—bring in heat. Single-pane glass, especially without shades or tinting, can create greenhouse-like conditions inside your rig, increasing your cooling demand.
- Insulation Quality: RVs with poor insulation lose cool air quickly and heat up faster. If your walls or roof aren’t well insulated—or if you camp in hot sun without much shade—you’ll want a unit that can keep up.
- Where You Travel: Dry climates like Arizona can still feel manageable with moderate cooling, but throw in Florida-level humidity and you’re suddenly asking a lot more of your system. Plan for the worst heat you expect to encounter, not just your average trip.
- Number of A/C Zones: If your RV uses more than one A/C unit (for example, a separate one in the bedroom), you may be able to go with lower BTU units in each zone. But if you’re relying on one unit to cool your entire rig, lean toward higher capacity.
- Roof Opening Size: Most rooftop A/C units fit a standard 14" x 14" opening, but some older or specialty rigs might differ. Always measure before assuming a new unit will slide right in.
- Roof Weight Limits: Higher-capacity A/C units often weigh more. If your RV’s roof is lightly framed—or just showing its age—installing a significantly heavier unit could strain the structure or require reinforcement.
- Thermostat Compatibility: Newer units sometimes require digital thermostats or brand-specific control systems. If your current wall thermostat isn’t compatible, be ready to upgrade and possibly rewire or replace your control panel. This can be a hidden cost and complication, especially when switching brands.
Even if your BTU math checks out, you still need to make sure your electrical system can handle the load. The key here isn’t just the running amps, but rather the startup amps. When your A/C first kicks on, it draws a much higher burst of power. If your system is already running other appliances (like a microwave, water heater, or converter), that surge can easily trip a breaker—especially on 30-amp service or when running on a generator.
In short, you can definitely upgrade A/C units or switch brands, but only after you’ve ticked off these important points. Finding a replacement doesn’t mean you have to stick with the same old thing; it’s all about ensuring your upgrade fits seamlessly with your RV, without turning the installation into a major renovation project.
Step 3: Know What You’re Buying
When you shop for a new RV A/C, you’re not just buying a single unit—you’re buying a system. And that system is often sold in pieces. If you don’t check what’s included (and what’s not), you could end up with half an install and a whole lot of frustration.
Here’s how the setup typically breaks down:
- Upper Unit (Rooftop Assembly): This is the big box that mounts on your roof. It houses the compressor, condenser, evaporator coil, and blower fan—basically everything that makes cold air happen. It connects to your interior ceiling assembly via a mounting gasket and bolts.
- Ceiling Assembly (Interior Kit): This piece mounts inside your RV, directly beneath the upper unit. It includes the air distribution box, return air filter, and user controls (like knobs, buttons, or digital displays). Some also contain a control board that communicates with a wall thermostat.
- Thermostat (if required): Many ducted systems (and some upgraded non-ducted ones) use a separate wall-mounted thermostat or digital controller. These aren’t always included, and not all upper units support every thermostat. Always check for compatibility before assuming your old one will work.
If you’re replacing an existing system, you might be able to reuse your current ceiling assembly or thermostat, but only if they’re compatible with your new upper unit’s voltage and control system and they come from the same brand and product series (or are verified cross-compatible).
Mixing and matching across brands or product lines is where shoppers tend to get burned. Remember, it’s not just about physical fit—the control boards, wiring, and voltage all need to line up too.
What to Check Before You Buy
Look closely at each product listing to confirm:
- What’s included: Is it just the upper unit? Or a complete kit? Read carefully.
- Voltage requirements: Most units are 110-120V, but double-check that it matches your RV’s electrical system.
- Thermostat notes: If the listing says “thermostat sold separately” or “requires digital control,” that’s your cue to add that item to your cart.
- Compatibility info: Check whether the product specifically lists the models or series it’s compatible with—especially important if you’re replacing just one part of an older system.
If specs are vague, don’t guess. Reach out to the manufacturer or retailer, especially if you're switching brands or systems. It helps to have your current model numbers handy for quick comparisons.
Before you hit “Buy Now,” take a moment to double-check dimensions, roof support, and compatibility across every component. Most units fit a standard 14" x 14" opening, but if your rig is older or custom-built, verify measurements before committing. It’s also worth confirming your power system can handle the load—and that your install plan (DIY or pro) is ready to go.
Step 4: Shop Smarter With Parts Via
When it’s time to buy, where you shop matters just as much as what you buy. At Parts Via, we carry the industry’s top brands—like Coleman-Mach, Dometic, and Furrion—and we work directly with the manufacturers. That means you get current model years, valid warranties, and no guesswork when it comes to compatibility or returns.
We also make the logistics easy. RV A/C units are bulky and pre-charged with refrigerant, so they can’t ship like your usual online order. With Parts Via’s fast, FREE ship-to-store option, you can have your new system delivered directly to a participating dealer or service center near you. Pick it up when it’s convenient, or schedule installation with a qualified technician and let them handle the heavy lifting.
And if you need help along the way? You’re backed by a nationwide network of RV pros who know the gear and understand the install. That’s the difference a specialized dealer makes.