Espar Airtronic D2 Diesel Heater Kit 7,500 BTU

Reliable Diesel Cabin Heat for Canadian Waters

The Eberspaecher Airtronic D2 diesel heater kit is purpose-built for marine environments, drawing on over 30 years of successful installations worldwide. Whether you're cruising the Great Lakes in late autumn, anchored off the coast of Nova Scotia in early spring, or living aboard through a mild West Coast winter, the D2 provides consistent, controllable warmth below deck. It runs on diesel fuel drawn directly from your main tank via the included fuel metering pump, so there's no need for a separate propane system or bulky electric heaters that drain your batteries.

Four Selectable Heat Levels for Precise Comfort

The Airtronic D2 offers four distinct thermal output settings, allowing you to dial in the right amount of heat for conditions on board. At its lowest setting, the heater produces 2,900 BTU (850 W) — enough to take the chill off a cool evening. At its highest "Boost" setting, it delivers a full 7,500 BTU (2,200 W) to warm the cabin quickly after a cold, wet day on deck. The intermediate settings of 1,200 W and 1,800 W provide useful mid-range options. This variable output also means the heater consumes only as much fuel and electrical power as the situation demands, helping conserve both diesel and battery reserves.

Complete Kit — Everything You Need for Installation

One of the key advantages of this kit is that it arrives with all the major components required for a marine installation. You won't need to source ducting, exhaust, or fuel lines separately.

• 3 metres (approximately 10 feet) of 3-inch flexible ducting
• Loose duct fittings for routing warm air to cabin outlets
• Copper fuel lines for reliable, corrosion-resistant fuel delivery
• Fire-resistant fuel adaptors
• 10 feet of double-wall stainless steel exhaust
• Digi-Controller with built-in diagnostics for easy operation and troubleshooting

Installation Considerations for Sailboats and Powerboats

On a sailboat, the compact Airtronic D2 is typically installed in a stern or cockpit locker, with the exhaust routed to the transom. Warm air ducts run behind panels and through interior lockers to cabin outlets. As the ducts pass through storage areas, natural surface heat loss creates useful drying compartments — a welcome bonus for damp foul-weather gear. Fuel is drawn from the main diesel tank, and consumption is so low it does not materially affect the fuel carried for the engine.

On a powerboat, the heater is normally installed in the engine area, with hot air ducted to the cabins via flexible tubes. All that's visible in the living spaces are the discreet warm air outlets. If your powerboat has a gasoline engine, a separate small diesel tank is recommended to supply the heater.

The heater operates within a permanent heel angle of 15° and can function after start-up at angles up to 30°, making it suitable for sailing conditions. The exhaust hull fitting should be positioned a minimum of 300 mm above the waterline to prevent water ingress.

Electrical Requirements and Battery Draw

The Airtronic D2 requires a 12-volt battery connection to power the initial ignition, fuel metering pump, and main air fan. Electrical consumption ranges from just 8 watts at the lowest heat setting to 34 watts at full output — a modest draw that balances effective heating with battery conservation. For boats with limited battery capacity, this economical power consumption means you can run the heater through the night without excessive drain on your house bank.

Digi-Controller with Diagnostics

The included Digi-Controller provides straightforward temperature management and includes a diagnostic function. This allows you to monitor heater status and identify any fault codes without additional equipment. The controller is designed for interior mounting in an easily visible and accessible location, such as near the chart table or instrument panel. Operating devices with integral temperature sensors should be positioned away from direct sunlight, galley heat, or draughts to ensure accurate readings.

Specifications

• Heat Output Range: 850 / 1,200 / 1,800 / 2,200 W (2,900 to 7,500 BTU)
• Voltage: 12V DC
• Air Flow Volume: 40 / 60 / 90 / 105 m³/h
• Electrical Power Consumption: 8 / 12 / 22 / 34 W
• Fuel Consumption: 0.10 / 0.15 / 0.23 / 0.28 L/h
• Dimensions (L × W × H): 310 × 115 × 122 mm
• Weight: 2.7 kg
• Fuel Type: Diesel
• Suitable Sailboat Length: Up to 26 feet (8 m)
• Suitable Powerboat Length: Up to 17 feet
• Ducting Included: 3 metres of 3-inch (approximately 75 mm) flexible ducting
• Exhaust Included: 10 feet of double-wall stainless steel exhaust
• Maximum Operating Angle (after start-up): 30°
• Permanent Operating Angle: 15°
• Minimum Exhaust Hull Fitting Height Above Waterline: 300 mm
• Maximum Fuel Line Length (to pump): 5 m (2 mm diameter)
• Maximum Fuel Line Length (pump to heater): 6 m (2 mm diameter)
• Warranty: 2 years / 2,000 hours, parts and labour
• MFG Part Number: 20.2820.69.0900.0Z

Key Features

• Four selectable heat levels — match output precisely to cabin size and weather conditions, from a gentle 2,900 BTU to a full 7,500 BTU
• Complete installation kit — includes ducting, exhaust, copper fuel lines, fuel adaptors, and controller so you can get started without sourcing parts separately
• Digi-Controller with built-in diagnostics — monitor cabin temperature and identify fault codes from a convenient interior-mounted panel
• Compact, lightweight design — fits easily into cockpit lockers and tight engine compartments common on smaller boats
• Economical fuel consumption — as low as 0.10 L/h at the lowest setting, so overnight heating barely affects your diesel reserves
• Low electrical draw — runs on as little as 8 watts, preserving battery capacity during extended anchorages
• Draws fuel from your main diesel tank — no separate propane bottles or dedicated fuel systems required on diesel-powered boats
• Operates at sailing angles — functions at permanent heel up to 15° and up to 30° after start-up, keeping you warm while under sail
• Double-wall exhaust system — insulated stainless steel construction helps manage heat and protect surrounding components
• Passive drying benefit — warm air ducts passing through lockers create natural drying compartments for wet gear
• Proven marine heritage — over 30 years of successful marine installations worldwide, backed by a comprehensive parts and labour warranty