Can a portable diesel heater keep your camper van warm for 24 hours straight on just 3.5 liters (under 1 gallon) of fuel? I put the Outequip all-in-one 5kW diesel heater to the test in my 2024 Mercedes Sprinter camper during near-freezing Texas weather. This unit features a superior Kyocera glow plug and quiet fuel pump for premium build quality. Here’s what happened.
The 24-Hour Challenge Setup
Filled the 5L tank with 3.5L diesel, hooked it to the starter battery via jump posts, and added a power meter to track Wh usage. Mounted on a tire step outside the driver window with my DIY wood template vent (spray paint + clear coat for rainproofing). Ran on settings 1-2 to simulate overnight comfort.
Watch the full test: Outequip Diesel Heater Test – 3.5L vs 24 Hours
Key Results
- Runtime: 19.7 hours until fuel empty (E2 code)—nearly hit the 24-hour goal!
- Fuel efficiency: 0.18 L/hour average. Full 5L tank = ~28 hours.
- Power draw: Just 237 Wh total (~12W avg on low). Setting 10 maxed at 46 Wh/hour.
- Inside temp: 65-66°F with 35°F outside, fan blowing. Cozy for movies, popcorn, and games—no fumes.
- Restart: Primed fuel pump (up arrow 3 sec), fired right up post-dry run.
Sprinter’s 94Ah battery laughs at this (1128Wh total)—uses <21% on low, stays >50% SOC easy.
All-in-One vs Split System
All-in-One wins for portability: 2-wire setup (12/24V or 110V adapter), no permanent mods. The Kyocera glow plug and quiet pump give it superior build quality over typical Chinese heaters. Perfect for van life trials, garages, or backups.
Get the All-in-One Diesel Heater
Discount: RAN20 ($20 OFF)
Best for quick plug-and-play. Remote battery: here.
Split for full builds: More efficient (no exposed hose losses), OEM look.
Get the 5KW Split System
Discount: RAN20 ($20 OFF).
Prebuilt Sprinter owners: No-Tank-Drop Hack (Unlisted).
Accessories I Use & Recommend
- Tire steps/tables for mounting: Tire steps, Tire table
- Ducting/exhaust: 8ft duct, siphon pump, exhaust options, wraps
- AliExpress extras: vents/ducts
After 3 weeks testing, Outequip Pro delivers reliable performance with easily available, affordable parts.
Snow day test coming Saturday. Which setup for you—van, RV, garage?
Full Sprinter Van Build Playlist | Free Parts List
As always, make it a great day!