17/20
Espar Airtronic AS3 D2L (0.5 US gal) 12V (17/20)
Top-tier pick at 17/20. The one to beat in winter gear.
C$2.14Checked Oct 6Check price
Guide
Diesel bunk heaters for winter
Real heat without idling. How they work, what they burn, and which ones survive a Canadian winter.
Updated October 5, 2026
Idling a big diesel all night to stay warm is the most expensive blanket ever sold. A diesel air heater — the same technology that's heated European truck cabs for decades — burns a thimble of fuel per hour and keeps the sleeper genuinely comfortable down to -40°C.
How they work
A diesel air heater pulls fuel from your tank, burns it in a sealed combustion chamber, and blows heated air into the bunk through a heat exchanger. Exhaust goes outside. The cab air never mixes with combustion gases — that's the entire safety proposition, and why they're legal where idling isn't.
The picks
12/20
VEVOR 8 kW 12V diesel air heater (all-in-one) (12/20)
Scored 12/20 in our winter gear rankings.
C$139.90Checked Oct 6Check price
The most expensive heat is the heat you burn diesel to make by idling.
What they cost to run
Expect roughly 0.1–0.3 litres of diesel per hour depending on heat setting and outside temperature. Over a 10-hour night that's 1–3 litres — against 3–4 litres per hour idling the main engine. The math isn't close. See the winter idling payback calculator for your numbers.
Installation reality
Plan a full day if you're handy, or budget for a shop install. You need: a fuel pickup (standpipe in the tank or a separate small tank), 12V power, an exhaust route through the floor, and a combustion air intake. The all-in-one units simplify this — everything lives in one box — at the cost of taking up cab space and being harder to service.
Questions, answered
Are diesel heaters safe in a sleeper?
Yes — combustion is sealed and exhaust goes outside. Install a CO detector anyway. It's cheap insurance.
How much fuel do they use?
Roughly 0.1–0.3L per hour. A 10-hour night costs 1–3 litres vs 30–40L idling.
Can I run it while driving?
Yes, that's what they're designed for — pre-heating the bunk and supplementing cab heat.
Deal alerts
Never pay full price again.
Price drops on the gear you actually want, in your inbox before they sell out.
Deal alerts aren't live yet — we're building real price tracking first. Check back soon.
— Marcus
Disclosure: The Driver Gear is reader-supported. When you buy through links on this page, we may earn an affiliate commission at no extra cost to you. Scores reflect our editorial comparison methodology — how we test.