YOUR ENERGY PROFILE.
This document contains the sizing of your future electrical installation, calculated based on your appliances.
Inventory:
Battery
To guarantee 0WH without damaging your bank (80% max discharge):
Solar
Minimum power required to recharge your consumption:
220V AC
Maximum power (with 25% safety margin).
12V Cable Sizing Guide
Use this professional reference table to select the correct gauge (mm²) for your cables. For 12V in a van, the maximum tolerated voltage drop is 3%. Always use multi-stranded flexible automotive wire.
| Current (A) | Round trip < 2m | Round trip 4m | Round trip 6m |
|---|---|---|---|
| 5A (LEDs, USB) | 1.5 mm² | 2.5 mm² | 4 mm² |
| 10A (Fridge, Pump) | 2.5 mm² | 4 mm² | 6 mm² |
| 20A (Heater) | 4 mm² | 10 mm² | 10 mm² |
| 50A (DC/DC Booster) | 10 mm² | 16 mm² | 25 mm² |
| 100A (Inverter) | 25 mm² | 35 mm² | 50 mm² |
Fuse Sizing
The fuse protects the wire, not the appliance. Always place it as close to the power source as possible (battery or busbar).
- Wire 1.5 mm² → Max fuse 10A
- Wire 2.5 mm² → Max fuse 20A
- Wire 4 mm² → Max fuse 30A
- Wire 6 mm² → Max fuse 40A
- Wire 10 mm² → Max fuse 60A
SCHÉMA ÉLECTRIQUE
PANNEAUX SOLAIRES
0W
REGULATEUR MPPT
BATTERIE AUXILIAIRE
0 Ah
Lithium LiFePO4
BOÎTE À FUSIBLES 12V
Pompe, Leds, Frigo...
CONVERTISSEUR 220V
NON REQUI
SHOPPING LIST
Where to find this equipment? Here is the community-approved selection.
12V 6-way Fuse Box
Mandatory protection
Digital Multimeter
Test your connections
Heavy Duty Crimping Tool
For perfect lugs
Heat Shrink Tubing
Insulation and safety
Comparison table
| Heater | Power | Diesel/h | 12V draw | Price |
|---|---|---|---|---|
| Webasto Air Top 2000 ST | 2kW | 0.10-0.24 L/h | 7-25W | $700-1,200 |
| Espar Airtronic D2 | 2kW | 0.09-0.24 L/h | 8-25W | $600-1,000 |
| Vevor 2kW (China) | 2kW | 0.10-0.28 L/h | 10-30W | $150-250 |
| Webasto Air Top Evo 40 | 4kW | 0.14-0.47 L/h | 8-30W | $900-1,500 |
About this tool
Diesel heaters for vans draw astonishingly little electricity — this is their core advantage over electric heaters, and it's worth understanding the exact numbers before dismissing them as expensive luxuries. A Webasto Air Top Evo 40 or Espar Airtronic D2 consumes 10-12W during steady operation. A 2000W electric fan heater would drain the same LiFePO4 100Ah battery 200× faster.
Electrical consumption profile in detail: The startup candle glow draws 15-25W for 90 seconds while preheating. The blower motor ramps to 60-70W as combustion initiates for 2-3 minutes, then settles at 7-12W for the rest of the heating session. An 8-hour winter night: (70W × 3min + 12W × 477min) = 3.5Wh startup + 95Wh running = 98.5Wh total electricity consumed.
Fuel consumption is the other side of the equation. At low setting (2000 BTU/hr), a quality diesel heater burns 0.12-0.18 L/hr. At medium (4000 BTU/hr): 0.24-0.35 L/hr. At high (8000 BTU/hr for the Air Top Evo 40): 0.43-0.55 L/hr. A 5-liter auxiliary tank supports: 27h at low, 14h at medium, 9h at high — approximately 3-4 full winter nights per 5L fill.
Why cheap Chinese diesel heaters are risky: The "Vevor" and "generic" diesel heaters sold at €80-150 use inferior glow plug alloys that fail at 500-800 starts vs Webasto's 3000+ cycle rating. The fuel pump diaphragm quality directly determines reliability below -15°C. Their ECU protections (low voltage, overheat) are less sophisticated. For light use (occasional weekend trips), they're acceptable. For fulltime van life in northern Europe winter, they become chronic headaches.
Installation critical points: Combustion air inlet must be separated from exhaust — the intake goes below the chassis or into clean outside air, never in the same compartment as the exhaust exit. Exhaust pipe must exit behind the vehicle or to the side — never at the front where forward motion could push CO back into the van. Fuel pickup tube must be angled at 45° into the main tank at the ¼-tank depth level to prevent dry-running.
Programming and remote control: modern diesel heaters (Webasto, Espar) integrate with Victron Cerbo GX via digital temp sensors, or run standalone with app-based timers (Bluetooth adapter, €30). Setting a timer for the heater to pre-warm 30 minutes before you wake up transforms van life comfort in winter without wasting fuel overnight.
Glow plug replacement interval: the most commonly replaced component. Best practice is replacing proactively at 800 starts regardless of apparent condition — a failed glow plug leaves you cold in the night.