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Houseboat air conditioners are reliable, easy to install, and better than ever. Plus, they’ve become a highly affordable option for mariners.
The best houseboat air conditioners are the MarinAire 16,000 BTU unit, the CMT CT-16 air conditioner, the Dometic 10,000 BTU retrofit AC unit, and the UFLEX variable-speed climate control system.
In this article, we’ll go over key facts about houseboat air conditioning units, along with four of the best options on the market today. Additionally, we’ll discuss heat pumps, the refrigeration cycle, and why to avoid evaporative cooling systems on your boat.
We sourced the information used in this article from the manufacturers of marine air conditioning systems. Additionally, we referenced refrigeration and marine HVAC guides to provide tips on choosing the best system for your boat.
Air Conditioning vs. Evaporative Coolers for Houseboats
Air conditioners and evaporative coolers are easy to confuse. Some companies use questionable language and describe evaporative coolers as air conditioners (which they ‘technically’ are), but this language is confusing and obsolete. Here’s the difference between the two systems and why air conditioning is preferable on boats.
Virtually all cooling devices rely on evaporation, and air conditioners are no exception. Air conditioners use the refrigeration cycle to draw heat out of the air. They don’t ‘add’ cold; they just take away heat. Air conditioners use a compressor, a condenser, and a set of tubes filled with refrigerant.
The boiling point of the refrigerant is extremely low at room temperature. To change this, the refrigerant is compressed, which raises the boiling point. Eventually, the refrigerant becomes a liquid briefly and evaporates again, drawing all the heat out of the air and turning into a gas. The compressor then cycles again and converts the gas to a liquid, starting the process over again.
Air conditioners are closed-loop systems, which means the working fluid (in this case, the refrigerant) and the mechanical compressor are sealed inside airtight containers. This keeps harmful refrigerants from escaping.
Evaporative coolers are simple devices that operate on the same principle that the human body uses to cool itself. Evaporative coolers, or ‘swamp coolers’ as they’re known in the United States, drip water onto a membrane and evaporate it using a fan.
The water converts from a liquid to a gas (water vapor) and draws heat out of the air, thus cooling it. Evaporative coolers are an excellent choice for homes in some parts of the country, but they aren’t a good option for boats. We’ll explain why later.
Best Self-Contained Air Conditioning Units for Houseboats
There are only a few reputable manufacturers of houseboat and marine air conditioning units, and all of their products are well-made and reliable. We looked at the market and chose four of the best multi-function marine air conditioning and climate control units available today.
1. MarinAire 16,000 BTU/H Self-Contained Air Conditioner
The MarinAire 16,000 BTU/H self-contained air conditioning unit is a top-quality climate control system that comes with virtually everything you need to heat and cool your houseboat. The model is controlled by a digital thermostat, and it also comes with a remote control.
Like other high-end marine HVAC systems, the MarinAire unit comes with titanium coils to avoid corrosion. This model has built-in pressure gauges and a compressor sound deadener to reduce noise. Additionally, this highly efficient unit comes with a 360-degree rotatable blower.
The MarinAire AC unit also functions as a heat pump and serves as a highly efficient way to electrically heat your boat. This is convenient because one unit replaces both an obsolete air conditioner and the furnace, which can save an enormous amount of money and fuel over an extended period.
2. CTM CT-16 Marine 115-Volt Air Conditioner
CMT is a well-known producer of marine heating, ventilation, and air conditioning systems. The CMT CT-16 marine air conditioner is a highly efficient and well-designed 16,000 BTU cooling unit that runs on 115-volt AC power.
This unit is suitable for use on houseboats, as it conserves power and works with marine electrical systems. It also functions as a heat pump by using reverse cycle technology. This unit has titanium coils, which protect them from corrosion over time.
The CTM CT-16 is a ‘drop-in’ replacement for numerous common air conditioning systems. This makes installation easy, especially in the relatively open machine spaces of a houseboat. Additionally, this model features 5-foot temperature sensing technology for even heating and cooling. This feature, which increases comfort, also reduces energy usage.
3. Dometic 10,000 BTU Air Conditioning Retrofit
Need to convert an existing air conditioner to a more efficient all-in-one climate control unit? If so, consider the Dometic 10,000-BTU air conditioner retrofit kit. This kit is an air conditioner and a heater, as reverse cycle functionality allows it to effectively reverse the refrigeration cycle and generate heat.
This self-contained air conditioner and heating unit is an ideal replacement for old and obsolete air conditioning systems, and it may be more affordable than repairing an old unit. The unit produces 10000 BTU of heat or AC, and it runs efficiently on 115-volt AC power.
Like many similar modern units, the Dometic air conditioning retrofit kit comes with a programmable thermostat that’s easy to install in place of an existing unit. This single-module heating and air conditioning unit works best when used to replace an 8,000 to 10,000 BTU AC unit or furnace.
4. UFLEX 16,000 BTU Variable Speed Drive Air Conditioner Unit
The UFLEX 16,000 BTU variable speed air conditioner is a behind-the-scenes workhorse designed specifically for marine use. This high-tech and efficient unit has heat pump functionality as well, thanks to its ability to reverse the refrigeration cycle.
The unit comes with built-in wifi to make it easy to wirelessly control. Additionally, you can operate this unit from a mobile device, and your houseboat will be at the ideal temperature before you even board it for a trip. This energy-efficient unit can also be powered by a ‘modest’ marine battery bank.
Why Air Conditioning is Better for Houseboats
Evaporative coolers are not closed-loop systems. This means that when they evaporate water, they pump the water vapor into the structure that they’re cooling. That’s why they get the name ‘swamp coolers’ as they age and algae begin growing inside them.
This works well in hot and dry places (such as the Arizona desert) but not so well in humid coastal areas. Humidity causes mold, and boats are particularly prone to humidity damage, and evaporative coolers worsen the problem. Additionally, they don’t work nearly as well in humid environments as water evaporates more slowly.
Air conditioning, on the other hand, causes condensation to form on the condenser. Condensation then drains out of the air conditioner, which effectively draws water out of the air and dumps it overboard.
In this way, air conditioners work as dehumidifiers which helps prevent damage and mold growth on boats. Plus, they blow much colder air than evaporative coolers, albeit with significantly more energy consumption.