Coleman Mach 3 Plus 13,500 BTU Ducted RV Rooftop Air Conditioner

The Coleman Mach 3 Plus is a 13,500 BTU rooftop air conditioner, and it's one of the workhorses of the RV world. If you camp in real heat, this is the unit you want overhead. It drops into the standard 14-inch by 14-inch roof vent opening that most travel trailers, fifth wheels, and motorhomes already have, so on a lot of rigs it's a straight bolt-in replacement for a tired old unit.

What sets the Mach 3 Plus apart is airflow. Coleman built this line to move a lot of cool air for a single rooftop AC, which is exactly what you need when the coach has been baking in the sun all afternoon and you want it comfortable before dinner. It's a standard cooling unit, no heat pump, so it does one job and does it hard.

You can run it two ways. Non-ducted, it blows straight down through a ceiling assembly into one open living area, which is the simple setup on smaller trailers. Ducted, it feeds your rig's existing overhead duct runs so the cool air reaches the bedroom and the far end of a longer coach. Same air conditioner, both setups. Which one you use comes down to how your RV is built and which ceiling assembly you pair with it.

On the electrical side, this is a 120-volt unit with a 13.1 amp compressor draw. That's normal for a 13,500 BTU rooftop AC, but it's worth knowing before you fire it up on a crowded 30-amp pedestal. If you're also running the microwave, the water heater on electric, and a coffee maker, you can trip the pedestal breaker. Nothing wrong with the AC, just the math of a 30-amp service. Plan your big loads and you'll be fine.

A couple of things this unit does not include, and you'll want to know up front. There's no heat pump, so it cools only. There's no condensate pump, which means the condensate drains off the roof the normal way and you route the drain so it sheds cleanly off the side of the coach. And the ceiling assembly is ordered separately. The AC is the rooftop chassis. The ceiling assembly is the interior half with the grille, the controls, and the filter, and you match it to your ducted or non-ducted setup. Order both together so you're not waiting on a second box mid-install.

It weighs 79.5 pounds and measures 38 inches long by 26.1 inches wide by 13.8 inches tall on the roof. That's a two-person lift up a ladder, and you want the roof structure around the vent opening to be sound before you set it down. Most RV roofs built for a rooftop AC handle this weight without a problem, but if you're converting an old 14-inch vent that never carried an air conditioner, check the framing first. The gasket seals against the roof around the 14-inch opening, so a clean, flat mounting surface matters for a leak-free install.

The finish is white, which is the standard look on most RV roofs. It matches the majority of factory installs, so a replacement doesn't leave you with an oddball unit up top. And because the footprint follows the common 14-inch pattern, the swap stays simple when it's time to upgrade an aging AC.

One note on the part number. This unit shows as 48203-066 and it's also cataloged under the newer number 38203-066. Same air conditioner, updated part number, so don't let the two numbers throw you if you're cross-checking against an older manual or a parts list.

Bottom line, the Mach 3 Plus is a lot of cooling in a proven package. If your rig runs hot and you want a rooftop unit that keeps up, this is a solid pick. Just remember to add the matching ceiling assembly to your order so the install goes in one shot.