Espar Airtronic S3 D2L heater kit with the heater, EasyStart Pro controller and installation kit boxes

Diesel heater air outlet in a cabinet base inside a Sandy Vans Sprinter build

Espar Airtronic S3 D2L 12V heater kit contents laid out: heater, fuel pump, exhaust, ducting and harnesses

Eberspaecher EasyStart Pro heater controller mounted on a wood wall in a van

Espar Airtronic heater with its box and installation kit parts

Heater air outlet next to the bench in a Sandy Vans Sprinter

Diesel heater air outlet in a wood box beside a van seat base

Sandy Vans galley build in a Sprinter heated by an Espar diesel heater

Sprinter van interior with a diesel heater outlet at the cabinet base

Diesel heater intake and outlet grills on a cabinet end panel

Espar

Airtronic AS3 D2L 12V Diesel Heater Kit

Name: Airtronic AS3 D2L 12V Diesel Heater Kit
SKU: ESPAR-SV
Price: 1499.0 USD

~~$1,699.00~~ $1,499.00 Save 12%

Shop 5.0 Shop rating (174) on Google

Product variants

Pickup available at Sandy Vans HQ

Usually ready in 2-4 days

Dry, quiet heat on a cold night, running off the diesel already in your tank.

The Espar Airtronic AS3 D2L is a 12V diesel air heater that puts out up to 7,500 BTU while sipping fuel from your van's tank. This is the complete kit: heater, EasyStart Pro controller, fuel pump, exhaust, intake, ducting and wiring, ready for a van build.

Fits: Diesel vans, including the diesel Mercedes Sprinter. Not compatible: Gas (petrol) or electric-only vans; Espar's kit is diesel only.

0.85 to 2.2 kW (2,900 to 7,500 BTU) of heat, adjusting to hold your set temperature
0.02 to 0.07 gal/h of diesel and 6 to 27 W of 12V power while running
Automatic altitude adjustment up to about 13,120 ft
EasyStart Pro controller with timer and temperature control
Complete kit: fuel pump, fuel pick-up tube, stainless exhaust and silencer, intake, ducting, grills and harnesses
2-year North American warranty

Heat that runs all night without draining your house batteries.

See it on your van. Add the Airtronic AS3 D2L 12V Diesel Heater Kit to your build in our 3D Van Builder and preview it on a real Sprinter before you buy.

Product Details

Why we put Espar heaters in our vans

Diesel air heaters are the most efficient way to heat a Sprinter overnight. The Airtronic AS3 burns a tiny amount of diesel from your van's tank, draws very little 12V power, and keeps the cabin at a steady temperature while you sleep. We've installed them in our builds for years.

How it works

The heater sits inside the van and pulls combustion air from outside, burns diesel in a sealed chamber, and sends the exhaust back outside. Cabin air passes over the heat exchanger and comes out through the ducting, so the air you breathe never mixes with combustion gases. The EasyStart Pro controller sets the temperature and timer, and the heater steps its output up and down to hold it.

Built for the road

Works at altitude, adjusting automatically up to about 13,120 ft
Quiet operation for sleeping
Runs on diesel, including HVO and GTL renewable diesel, per Espar

Fitment & Compatibility

Fits: Diesel vans, incl. the diesel Mercedes Sprinter

Not compatible with: Gas (petrol) and electric-only vans

Not sure your build qualifies? Reach out to our team.

Specifications

Brand	Espar (Eberspaecher)
Model	Airtronic S3 D2L, 12V
Fits	Diesel vans, incl. diesel Mercedes Sprinter
Heat output	0.85 to 2.2 kW (2,900 to 7,500 BTU)
Fuel	Diesel (HVO and GTL compatible)
Fuel consumption	0.02 to 0.07 gal/h (0.10 to 0.27 L/h)
Power draw	6 to 27 W while running, 12V
Altitude	Automatic adjustment up to about 13,120 ft
Heater dimensions	12.2 x 4.5 x 4.8 in
Controller	EasyStart Pro
Part numbers	Heater 252953050000; install kit 252029800000
Warranty	2-year North American warranty

What's in the Box

Espar Airtronic S3 D2L 12V heater
EasyStart Pro controller
12V fuel pump
Fuel hose
Fuel pick-up tube (600 mm)
Exhaust silencer
Stainless steel exhaust (about 6.6 ft)
Combustion intake pipe (about 3.3 ft)
60 mm flexible ducting (about 1.6 ft)
Inlet grills and 60 mm air outlet grill
Plug-and-play wiring harnesses
Screws, clips and straps
Installation manual (QR download)
Warranty documentation

Install Time7 to 8 hours

DIY FriendlyAdvanced; professional install recommended

Drilling RequiredYes, floor openings for exhaust and intake

A diesel heater install means drilling through the floor for exhaust and intake, tapping fuel, and wiring to your 12V system. Plan on a full day. The Espar installation manual comes with the kit (scan the QR code on the included card to download it).

Planning the install

Mount the heater inside the van, on a solid floor, with room for the exhaust and intake to exit underneath.
Route the exhaust away from doors, windows and the intake, and keep it clear of fuel and brake lines.
Insulate exterior fuel lines and connections so they don't crack.

Mistakes to avoid

Installing in a gas van. This kit is diesel only.
Exhaust near an opening. Keep the exhaust outlet away from doors, windows and the combustion intake.
Undersized wiring. Wire to Espar's spec in the manual.

Want us to install it? Reach out to our team at products@sandyvans.com or (619) 812-1903.

Tools You'll Need

See the Espar installation manual for the full tool list

See all Sandy Vans install videos & manuals →

How to choose a diesel heater for your van

1. What fuel does your van run on?

How to choose: A diesel heater fits a diesel van and draws straight from its tank. Gas vans need a different setup.

2. How much heat do you need?

How to choose: A 2.2 kW (7,500 BTU) heater is the common size for a Sprinter-sized camper. Larger or poorly insulated spaces may need more.

3. Will you camp at altitude?

How to choose: Pick a heater that adjusts automatically for altitude if you camp in the mountains.

4. How do you want to control it?

How to choose: A controller with a timer and thermostat lets you wake up to a warm van.

Before you order

Diesel van confirmed
Heater location planned with room underneath for exhaust and intake
Install plan: DIY or professional

How the Airtronic AS3 stacks up

Fuel: diesel, straight from your tank.
Output: 2,900 to 7,500 BTU, self-adjusting.
Altitude: automatic to about 13,120 ft.
Control: EasyStart Pro controller included.

Will it work in my gas Sprinter?

No. This kit is diesel only and isn't suitable for gas or electric-only vans. Reach out to our team at products@sandyvans.com or (619) 812-1903 to talk through options.

How much diesel does it use?

Between 0.02 and 0.07 gallons per hour depending on the heat setting.

Will it drain my batteries?

It draws 6 to 27 W while running. Startup draws more for the first minute or two while the glow plug heats up.

Does it work at altitude?

Yes. It adjusts automatically up to about 13,120 ft.

What's in the kit?

The heater, EasyStart Pro controller, fuel pump, fuel hose and pick-up tube, stainless exhaust with silencer, combustion intake pipe, 60 mm ducting, inlet and outlet grills, wiring harnesses, mounting hardware, and the installation manual.

Can you install it for me?

Reach out to our team at products@sandyvans.com or (619) 812-1903 to talk about installation.

Do you install products for customers?

Yes. Many SV products can be professionally installed at our San Diego shop. Reach out to our team to schedule. Email products@sandyvans.com or call 619-812-1903.

What is your shipping and return policy?

Most SV products ship free. For returns, see our Returns & Refunds policy or reach out to our team at products@sandyvans.com.

Can I reach a real person with questions?

Always. We are a small team in San Diego. Email products@sandyvans.com or call 619-812-1903 and you'll get a real answer, not a chatbot.

Where are you located?

9393 Trade Pl, San Diego, CA. Come visit the shop, we'd love to show you around.

Does Sandy Vans offer financing?

Yes. Many financing options are available. Set up a call with a sales associate to learn more.

Still have a question? Email the team and you'll get a real answer.