How to Install a Diesel Heater in Your Van

# How to Install a Diesel Heater in Your Campervan *Published: May 20, 2026 · Tutorial · 10 min read*  heating your campervan is one of the most important decisions you'll make as a van lifer. With the UK's damp, chilly winters, a reliable heating system can mean the difference between cozy mornings and shivering through frost. Diesel heaters have become the gold standard for van life heating — affordable, efficient, and powerful enough to warm even the largest conversions. In this comprehensive guide, we review the top diesel heaters available on Amazon UK, comparing their power output, fuel efficiency, noise levels, and value for money. Whether you're running a simple VW Transporter or a full-width Westfalia, there's a heater on this list for you. ## What You'll Need ### What to Look for in a Campervan Diesel Heater **Power Output (kW):** The most critical specification. A 5kW heater is sufficient for small vans (up to 10m³), while larger conversions need 9kW or more. The UK's cold, damp conditions mean you should err on the side of power. **Fuel Type:** Most UK diesel heaters run on 12V DC, drawing power from your leisure battery. Some dual-voltage models also accept mains power for base-camping. **Noise Level:** Critical for overnight use. Look for heaters under 49dB on high — anything louder will disturb your sleep. **Thermostat:** A built-in thermostat maintains your desired temperature automatically. External thermostats give more accurate readings. **Installation:** DIY-friendly models come with mounting kits, fuel lines, and exhaust pipes. Professional installation costs £150–£300. **Warranty:** Reputable brands offer 2–5 years. Budget Chinese models often have limited UK support. ## Step by Step ### DIY Installation: Step by Step 1. **Choose your location.** Under-seat mounting is most common. Ensure clearance for the exhaust pipe. 2. **Mount the heater.** Use the included brackets and self-tapping screws. Vibration pads help reduce noise. 3. **Run the fuel line.** From your diesel tank to the heater's fuel pickup. Use 6mm fuel hose and a fuel filter. 4. **Fit the exhaust.** Aluminium or stainless steel, angled downwards to shed rain. 5. **Wire the power.** 30A fuse within 150mm of the battery. Use 4mm² cable. 6. **Add the thermostat.** Mount on the interior wall, away from direct heat. 7. **Test run.** Fill with fuel, power on, and verify ignition sequence. ## Final Thoughts ### Top Pick: Warm Air 9kW **Pros:** - Incredible value at under £100 - Powerful 9kW output heats large vans quickly - Dual voltage (12V/220V) for flexibility - Auto thermostat with digital display - Quiet enough for overnight use at 49dB **Cons:** -塑料 housing may degrade over time - No remote thermostat included - UK warranty support is limited - 52dB on high is noticeable ### Best Premium: Webasto Thermo 900 DT **Pros:** - German engineering with legendary reliability - Industry-leading 44dB noise level - Digital display with self-diagnostic - Proven in commercial vehicles for decades - 5-year warranty **Cons:** - Premium price at ~£900 - Requires professional installation - Heavier than budget alternatives