AUTOTERM Air 2D 12V connections

This is the 12 V diesel AUTOTERM Air 2D, including its supplied electrical harness. The technical table, page 32, distinguishes the 12 V and 24 V versions. Its 0.8–2 kW figure is delivered heat; electrical running power is 10–29 W. The catalog uses 29 W / 12 V, approximately 2.42 A, for the upper running load. The reviewed manual does not quantify glow-plug startup current, so the energy estimate does not establish startup cable sizing.

The positive and negative terminals represent the battery end of the supplied loom. The AIR-2D-12 diagram, page 38, shows 25 A fuses in both the red positive and black return legs. Retain that harness arrangement; do not replace it with a generic two-wire running-current circuit. The catalog's 25 A terminal boundary describes this protected harness, not the heater's consumption or an independently verified connector rating. The controller, temperature sensing and pulsed fuel-pump wiring remain on their dedicated loom connectors.

The electrical installation, page 20, calls for protected, dry routing and recommends a direct battery connection. Remove fuses while making connections and inspect the full circuit before restoring power. Avoid a switch or battery disconnect that removes the feed while the heater is running.

Use the manual's combustion-air, exhaust, fuel and heated-air layouts together. Combustion exhaust must remain outside occupied space and clear of air intakes; the cabin-air intake must not draw exhaust from an engine compartment. Check hose orientation, mounting clearances and the specific vehicle or boat installation requirements before drilling. Electrical completion alone does not make a heater installation ready to use.

Stop the heater with its controller and let the automatic purge finish before isolating battery power. For starting failures, measure voltage at the heater during the attempt and inspect both fused supply legs before replacing parts. The service guidance, page 27, calls for inspection of corrosion, fuel and exhaust connections and a monthly full-power run of about 20 minutes. The same page gives 30–40 mA standby consumption; account for that separately during long storage.