Air-to-Water air conditioning Titanium heat exchanger for Boat, Yacht, Waterfront home, Island home, or Solar Geothermal Home - no noisy generator or inefficient inverter, even solar!  In the past, comfort required staying tethered to shore power on the dock in a marina. But you purchased the boat to explore and enjoy peaceful, even exotic, remote anchorages. Then you discovered that meant running a large, noisy, diesel-hungry, expensive, high-maintenance generator 24/7 while cruising and at anchor, completely polluting the sounds of peaceful anchorage.

Imagine navigating by day in a comfortably air-conditioned/heated helm while recharging batteries and desalinating enough water for the evening. (See our 48v DC Direct Water-Maker.) After dropping anchor for the evening, you redirect that energy to cool down the salon and galley to a perfect temperature while preparing dinner, and enjoying cocktails with a movie without the background drum of a generator running. After the movie, you open the salon doors to let the evening air swirl through the salon while retiring to your quiet bug-free air-conditioned cabin for a restful night's sleep.

~Equivalent to 32 to 42 SEER! Our DC-Direct Chillers are ABSOLUTELY the MOST EFFICIENT solution available or manufactured anywhere worldwide!  Chillers with separate air handlers are well known to be the most efficient solution to heating and air conditioning. Our unique 48v / 24v DC-Direct Marine Air to Water Heat Exchangers utilize power from DC solar and DC battery sources without wasting 20% to 50% on 2 to 5 conversions before it reaches the unit, compared to AC-powered units.

Availability: First 8 units have arrived!   Five 48V 16,000 BTU, two 24V 12,000 BTU, and one 9000 BTU!  All Sizes available MADE to ORDER - 3 Months to Delivery. 50% minimum to order, 50% balance due when ready to ship.

How is this Dream Possible?

A marine water chiller functions like an open-loop geothermal heat exchanger.  Read Why is DC-Direct better?

1. The 48v DC 24,000 BTU Titanium Water Chiller is installed in the Yacht's engine room or bilge storage area. The chiller transfers heat from the internal water-glycol system to the exterior raw water for cooling or reversed for heating. A water-to-water heat exchanger is essentially two water pipes, isolated from each other,  transferring heat through a membrane without mixing, and circulation pumps. It's internally closed-loop, so not affected by the hot, humid air of the engine room or bilge.
2. Each space on your yacht (cabins, salon, indoor helm) that needs cooling or heating receives its own appropriately sized, very quiet air handler (essentially a radiator, fan, and thermostat/humidistat). This naturally zoned system makes it possible to only cool or heat one or more occupied cabins at night or only the salon or helm by day and not the entire boat!
3. A single insulated pipe originating at the water chiller, or an optional Thermal Energy Storage Buffer Tank is fed by a circulation pump and loops around the boat connecting each air handler in series and then terminating at the water chiller.
4. When the thermostat/humidistat of any of the air handlers turns on,  it turns on the circulation pump

Features

• Simplicity = Low maintenance! Turns off when the chilled water temperature difference between inlet & outlet reaches 41℉
• Titanium Heat Exchanger - much longer life over nibrol especially in saltwater environments
  
• The compact size and option of multiple units in parallel make installation in an already cramped engine room or bilge storage space easier.
• Infinitely Variable from 3,000 to 24,000 BTUs - internally contains two 12,000 BTU stages, each automatically and independently adjusting to available power and demand. Chiller operates on 1 compressor if the demand is less than 12,000BTU
• Plumb 2, 3, 4 or more in parallel for larger vessels that require 48,000 BTUs, 73,000 BTUs, or  96,000 BTUs or more.
• The noise and heat generated by the compressors is removed from the living space, improving efficiency and blissful silence.
• Brushless DC circulation pumps are smaller and naturally variable speed, with less internal resistance, so more efficient, and up to 10x longer lasting than brushed AC pumps.

Quality Components

• Titanium Condensing Coils
• Stainless Steel Plate-Type Heat Exchanger Evaporator
• Two 12,000 BTU 48v DC Rotary Compressors
• Thermal Expansion Valve
• R134a Refrigerant
• DC Controls - High / low-pressure switches, gauges, safety valves

Ultra-durable, high-efficiency marine air conditioner designed for yachts, offshore platforms, and vessels. Featuring 48V DC inverter technology, a titanium alloy condenser tube, and a corrosion-resistant stainless steel housing, this system delivers fast cooling, reliable heating, and energy-efficient performance. Built for harsh marine environments, it integrates WiFi remote control, low-noise operation, and intelligent electronic expansion valve technology for seamless climate management.

 

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A high-performance, energy-efficient marine air conditioner designed to meet the demanding cooling and heating requirements of offshore vessels, yachts, and marine platforms. Engineered with 48V DC inverter technology, this unit provides stable temperature regulation, fast cooling, and optimized energy savings, making it ideal for marine and offshore environments.

With a cooling capacity of 12000BTU and heating capacity of 13450BTU, the MAR-48V/12BP ensures superior climate control in both hot and cold conditions. It features a titanium alloy condenser tube heat exchanger, offering exceptional corrosion resistance against seawater exposure. The 304 stainless steel housing with electrophoretic anti-corrosion treatment further enhances its durability, allowing it to withstand the harshest marine conditions.

This unit is equipped with an IP68-rated waterproof centrifugal vortex outer rotor motor, ensuring low noise operation for a quiet and comfortable onboard experience. Additionally, its smart electronic expansion valve improves refrigerant flow efficiency, increasing cooling performance and system longevity.

Supports WiFi remote control, allowing users to monitor and adjust temperature settings effortlessly through a mobile application. With robust construction, intelligent control systems, and premium components, this marine-grade air conditioner guarantees long-lasting performance, rapid cooling, and maximum energy efficiency.

Features

• 48V DC Technology – Provides precise temperature control, reduces energy consumption, and extends compressor lifespan
• Titanium Alloy Condenser Tube Heat Exchanger – Offers exceptional resistance to seawater corrosion while enhancing heat exchange efficiency for faster cooling
• High Cooling and Heating Capacity – Delivers 12000BTU cooling and 13450BTU heating, ensuring optimal comfort in extreme conditions
• Corrosion-Resistant 304 Stainless Steel Housing – Ensures long-term durability in harsh saltwater environments with electrophoretic anti-corrosion coating
• IP68 Waterproof Centrifugal Vortex Outer Rotor Motor – Operates efficiently with minimal noise, providing a quiet and comfortable experience
• Smart Electronic Expansion Valve – Optimizes refrigerant flow to enhance cooling efficiency and reduce system wear
• WiFi Remote Control Capability – Allows users to adjust temperature, monitor performance, and change settings via a dedicated mobile app
• Energy-Efficient and Eco-Friendly Refrigerant – Utilizes R410A refrigerant, ensuring an environmentally friendly cooling solution
• Brushless Circulation Pump - 2400L/H for 16,000 BTU and 12,000 BTU, and 1900L/H for 9000 BTU

Application Scenarios

• Luxury Yachts and Sailboats – Provides high-efficiency cooling and heating for a comfortable onboard experience
• Fishing Boats and Commercial Vessels – Maintains stable climate control for crew comfort
• Houseboats and Liveaboard Vessels – Ensures consistent air conditioning for extended stays
• Marine HVAC Systems for OEM and ODM Suppliers – Customizable for boat manufacturers and marine air conditioning providers

 

Power Supply 110V or 220V
Model	AC-110V-09DP	AC-110V-12DP	ACR-220V/16DP	ACR-220V/24DP
COOLING CAPACITY	9000 BTU	12000 BTU	16000 BTU	24000 BTU
HEATING CAPACITY	10450 BTU	13450 BTU	17450 BTU	25150 BTU
POWER SUPPLY (AC)	110V/220V 1ph/50Hz	110V/220V 1ph/50Hz	110V/220V 1ph/50Hz	110V/220V 1ph/50Hz
RATED POWER INPUT	850W	1147W	1236W	1810W
RATED CURRENT	7.8A / 3.9A	9.98A	11.23A/6.3A	16.8A/8.4A
MAX. POWER INPUT	950W	1227W	1790W	2050W
REFRIGERANT	R410A/420g	R410A/560g	R410A/670g	R410A/960g
Decibel of noise	42/52dB(A)	42/52dB(A)	42/55dB(A)	42/58dB(A)
AIR VOLUME	560m3/h	650m3/h	650m3/h	880m3/h
WATER FLOW VOLUME	720L/h	1080L/h	1250L/h	1900L/h
ANTI-SHOCK GRADE	I	I	I	I
WATER-PROOF GRADE	IPX4	IPX4	IPX4	IPX4
Dimension (L*D*H)(mm)	480×330×335	590×345×345	590×345×345	660×425×480
NET/GROSS WEIGHT	20/26 Kg	26/30.5 Kg	28/32 Kg	45/47 Kg

Q&A

What are the plumbing recommendations to each heat exchanger?

Following apply to 9000 BTU to 16,000 BTU heat exchangers. Upsize for larger

• Use 3/4" PEX A to minimize resistance to flow, easier installation with greater flexibility, and maximize reliability with vibration. Requires Pex A Expansion tool.
• Use 3/4 inch to 1/2 reducer on heat exchanger's 1/2 inch inlet pipe. 3/4" PEX A Can be placed directly on heat exchanger's 3/4 outlet pipe.
• Use 1 strainer oversized to handle the capacity of all heat exchangers (see Max flow rate with tables below) or 1 3/4" strainer for each heat exchanger
• Use 1 Brushless DC high-efficiency circulation pump per heat exchanger to maximize reliability and minimize complexity while allowing variation from only one heat exchanger to all running simultaneously

What are the Thru-hull Inlet Recommendations?

Heat Exchanger Size	Flow per Pump (GPM)	Max on 3/4" Inlet	Max on 1" Inlet	Max on 1.25" Inlet	Max on 1.5" Inlet	Max on 2" Inlet
Flow at 6 ft/s 30% Fouled		5.8 GPM	10.3 GPM	16.1 GPM	23.2 GPM	41.2 GPM
9,000 BTU	3	1 (3 GPM)	3 (total 9 GPM)	5 (total 15 GPM)	7 (total 21 GPM)	13 (total 39 GPM)
12,000 BTU	4	1 (4 GPM)	2 (total 8 GPM)	4 (total 16 GPM)	5 (total 20 GPM)	10 (total 40 GPM)
16,000 BTU	5.33	1 (5.33 GPM)	2* (limited to 10.3 GPM)	3 (total 15.99 GPM)	4 (total 21.32 GPM)	7 (total 37.31 GPM)
18,000 BTU	6	1* (limited to 5.8 GPM)	1 (6 GPM)	2 (total 12 GPM)	3 (total 18 GPM)	6 (total 36 GPM)
24,000 BTU	8	0*	1 (8 GPM)	2 (total 16 GPM)	2 (total 16 GPM)	5 (total 40 GPM)

*Marginal or cannot run without exceeding when 30% fouled; use larger inlet.

Assumptions and Calculations:

• Maximum flow (Q_max in GPM) = (V_max × ID²) / 0.408
  

  Inlet Size	Q_max at 5 ft/s (GPM)	Q_max at 6 ft/s (GPM)	Fouled Q_max at 5 ft/s (GPM)	Fouled Q_max at 6 ft/s (GPM)
  3/4"	6.9	8.3	4.8	5.8
  1"	12.3	14.7	8.6	10.3
  1.25"	19.1	23.0	13.4	16.1
  1.5"	27.6	33.1	19.3	23.2
  2"	49.0	58.8	34.3	41.2

  
  
• Per-pump flow rates (from guidelines for tropical conditions with fouling): 3 GPM (9,000 BTU), 4 GPM (12,000 BTU), 5.33 GPM (16,000 BTU), 6 GPM (18,000 BTU), 8 GPM (24,000 BTU).
• Thru-hull inner diameters (ID) approximate nominal sizes for standard bronze or composite fittings: 3/4" ≈ 0.75", 1" ≈ 1", 1.25" ≈ 1.25".
• Numbers are the maximum identical pumps that can run simultaneously without exceeding Q_max. If mixing types, sum their flows and compare to Q_max (e.g., one 9k + one 12k + one 16k = 12.33 GPM, which fits a 1" or larger inlet but not 3/4").
• Manifold should be at least as large as the inlet (e.g., 1" manifold for 1" inlet) with branches sized to each pump's hose (3/4" PEX). Use check valves to prevent backflow if not all pumps run together.
  

What are Inlet water temperature limits for Cooling and Heating?

When Cooling, inlet water temperature must be >68℉ (20°C). When heating, inlet water temp must be above freezing or >34℉ (2°C).  The minimum storage temperature for the closed loop circulation between air handlers and chiller is based on glycol/water mix used.

How to Heat when temperatures drop below freezing?

For heating below freezing, the exterior raw water circulation pump is left off. Instead a water heater (electric, diesel, LPG, or natural gas boiler) is used in the interior distribution loop. 

With this system, can I use waste heat off the engines or generator to heat the boat?

YES, you can use waste heat off your main propulsion or generator engines by adding a passive heat exchanger between the engine coolant and the interior distribution loop. With some creative plumbing (bypass valves), a portion of the propulsion engine coolant could be passed through the raw water intake of the chiller (unsupported, could void warranty).