Espar Airtronic AS3 B2L 12V Gasoline Heater - Full Kit

A genuine Eberspächer gasoline air heater with the complete install kit — for gasoline vans, where a diesel heater means carrying a separate fuel can.

If your van runs on gasoline, this is the heater that runs on the fuel already in it. The Espar Airtronic AS3 B2L draws from the vehicle’s own gasoline supply, so there is no auxiliary tank to fill, no jerry can rolling around the garage, and no second fuel to think about.

It puts out 6,824 BTU (2.0 kW), draws 11–26 W while running, and burns 0.04–0.07 gal/h. Those numbers are the whole argument for a fuel-burning heater over an electric one: it will heat a van all night on a fraction of the energy a resistive heater needs, and it barely touches the house battery.

Diesel or gasoline — and will it fit your van?

• Buy the B2L (gasoline) if your van has a gasoline engine — a Ford Transit EcoBoost, a gasoline Sprinter, a ProMaster.
• Buy the D2L (diesel) if your van is a diesel. Do not mix them up; the fuel pickup and the burner are fuel-specific.
• Check the Transit note in the fitment table before you order for a Transit.
• Budget for a fuel line insulation wrap — it is not in the kit and we recommend it.

Vehicle fitment and fuel pickup

These full kits are designed for 2007+ Mercedes Sprinter, 2014+ Ram ProMaster and 2015+ Ford Transit vans. The fuel pickup is where the platforms differ, and it is the part of the job that decides your weekend — read the fitment table before you order.

Specifications

Full documentation — install instructions, operating instructions, technical sheet, troubleshooting guide, spare parts list, repair instructions, and the complete Easy Start Pro controller guides and wiring diagram — is available with the product. Ask us if you want it before you order so you can plan the install.

Package contents

• Espar AS3 B2L 12V heater (gasoline)
• Install kit — AIRTRONIC S3 B2L 12V
• Control kit — Easy Start Pro controller with adaptor
• Exhaust muffler, 24 mm
• Muffler clamps, 26–28 mm (2)
• Fuel line adapter, 7.5 mm to 3.5 mm
• Gasoline fuel pickup (standpipe)

Installing it: the fuel pickup is the job

Everyone worries about the heater. The heater is the easy part — it is a 5.5 lb box with four bolts, an intake, an exhaust and a loom. The job is the fuel pickup, and how hard it is depends entirely on which van you have.

On a Sprinter or a ProMaster there is a factory auxiliary fuel port and the supplied hoses clamp to it. On a Transit you are dropping the fuel tank to add a pickup pipe, which is a different scale of work — a lift or a very good set of stands, a nearly empty tank, and a friend.

• Size your positive feed and fuse for the ~30 A glow plug startup draw, not the 11–26 W running draw.
• Wrap exterior fuel lines and connections with insulation. Espar recommend it and we have seen unwrapped lines crack in a cold snap.
• The muffler can be mounted either way round; follow the guidelines for undercarriage mounting.
• Mount the heater where you can service it. A heater buried behind a fixed bed is a heater you will grow to resent.
• Keep the exhaust exit away from door openings and away from where you would sit outside the van.

Questions we get asked about this part

Are these genuine Eberspächer units?

Yes. Not all Espar kits on the market are built the same. These are genuine Eberspächer heaters supplied with high-quality Eberspächer wiring harnesses, rather than a genuine heater bundled with a generic harness.

Will it flatten my batteries?

Running, no — rated power consumption is a handful of watts, which is nothing next to a compressor fridge. Starting, briefly yes: the glow plugs draw roughly 30 A at startup for the first minute or two. Size your wiring and your fuse for the startup draw, not the running draw. That is the single most common electrical mistake on these installs.

How high can I take it?

The kit includes an altitude sensor and the heater is rated for automatic altitude compensation up to 13,120 ft (4,000 m). That covers every paved pass in the continental United States. Without altitude compensation, a fuel-burning heater runs rich at elevation and sooties itself up.

Which way round does the muffler go?

The included muffler does not mark a flow direction. Espar have confirmed it can be mounted in either orientation. What does matter is following the installation guidelines for undercarriage mounting — getting the exhaust routed, supported and terminated correctly is more important than the muffler’s rotation.

Can I use this on a diesel van?

No. Buy the AS3 D2L, which is the diesel version. The burner and the fuel pickup are specific to the fuel.

Why does the Sprinter kit come with a standpipe rather than a T-piece?

Because that is how this kit is configured. The supplied hoses are designed to attach to the factory auxiliary port with clamps. If a T-piece style connection suits your install better, the Dorman 800-188 auxiliary fuel connector adapter is the part people usually source.

Pairs well with

• Van heating, ventilation and conversion parts

Sold and shipped by Campervan Parts R Us, the parts counter of Noke Van Co. — a working van conversion shop in Roanoke, Virginia. If you are unsure whether this fits your van, email us the year, model and wheelbase and we will check it against a build sheet before you order.