Autoterm Heater Installation: Common Mistakes to Avoid (With Video Timestamps)

Installing an Autoterm diesel heater is one of the best upgrades you can make to a van or camper — but only if it’s installed properly.
In this detailed YouTube video, the installer walks through a full Autoterm heater installation and highlights the most common mistakes customers make, many of which cause noise issues, fault codes, poor heat output, or even safety risks.

👉 All credit goes to the original YouTube creator for this excellent, honest walkthrough:
🎥 Watch the full video here:
https://www.youtube.com/watch?v=UndXlOJCoCw&t=1s

Below, we’ve broken down the key Autoterm heater installation mistakes, explained why they’re a problem, and pointed you to exact timestamps in the video so you can jump straight to what matters.

Installing the Heater in the Wrong Orientation

⏱ Mistake shown at: 04:00

This is one of the most common Autoterm heater mistakes — and one of the easiest to avoid.

Autoterm heaters must be installed in a specific orientation so condensation can drain correctly and combustion works as designed. Getting this wrong can lead to:

• Hard starting

• Smoking

• Reduced heater lifespan

▶ Orientation is explained at 03:48, followed immediately by the mistake at 04:00.

Choosing the Wrong Mounting Location

⏱ Mistake appears around: 04:00

Mounting the heater wherever there’s space might seem fine, but poor placement can cause airflow problems and make servicing difficult later on.

The video shows better mounting options earlier at 00:48, then highlights what not to do shortly after.

Incorrect Fuel Tank Connection

⏱ Mistake shown at: 12:27

Fuel supply issues are behind many Autoterm heater problems, especially when the fuel pickup is installed incorrectly.

Common mistakes include:

• T-ing into unsuitable fuel lines

• Using unreliable pickup points

These often cause:

• Fuel starvation

• Failed starts

• Random shutdowns

▶ Mistake shown at 12:27
▶ Preferred fuel sender connection explained at 15:13

Fuel Pump Installation Errors (Noise & Performance Issues)

⏱ Mistake shown at: 17:37

If your Autoterm fuel pump is loud, this section is for you.

Common errors include:

• Incorrect pump angle

• Solid mounting to the chassis

• Poor location choice

These mistakes lead to:

• Loud ticking inside the van

• Inconsistent fuel delivery

▶ Mistake highlighted at 17:37
▶ Correct installation shown at 18:30

Air Intake Positioned Incorrectly

⏱ Mistake shown at: 19:46

The combustion air intake is often overlooked, but its position matters more than most people realise.

Poor intake placement can:

• Pull in hot air

• Suck in road spray or dirt

• Reduce heater efficiency

▶ Intake discussed at 19:35
▶ Mistake shown at 19:46

Exhaust Installation Mistakes (Multiple Critical Errors)

⏱ Mistakes shown at: 20:45, 21:34, 22:10

Exhaust routing is where many DIY installs go wrong — and it’s also one of the biggest safety concerns.

The video highlights several exhaust mistakes, including:

• Exhaust too close to plastic or fuel lines

• Poor routing under the vehicle

• Unsafe outlet positioning

These can lead to:

• Heat damage

• Carbon monoxide risks

• MOT or safety failures

▶ Mistakes shown at 20:45, 21:34, and 22:10
▶ Correct exhaust outlet positioning explained at 21:58

Electrical Wiring Mistakes

⏱ Issues appear after: 22:48

Electrical mistakes don’t always show up immediately — but they often cause:

• Intermittent heater operation

• Startup failures

• Fault codes later on

This section connects directly to the fault code example later in the video.

Fault Code 13 – Usually an Installation Issue

⏱ Shown at: 25:53

Fault Code 13 is a common Autoterm error, and it’s often blamed on the heater itself.

In reality, it’s usually caused by:

• Fuel supply problems

• Poor air intake or exhaust setup

• Electrical connection issues

▶ Fault code explained at 25:53

Poor Heat Output Due to Airflow Mistakes

⏱ Mistakes shown at: 27:33 and 28:09

If your heater runs but doesn’t heat well, airflow is often the issue.

Mistakes here can cause:

• Weak heat output

• Uneven heating

• Overworking the heater

▶ Mistakes highlighted at 27:33 and 28:09

Switching the Heater Off Incorrectly

⏱ Mistake shown at: 28:33

Diesel heaters need a proper cool-down cycle. Cutting power too early can:

• Cause carbon buildup

• Damage internal components

• Shorten heater lifespan

▶ Mistake shown clearly at 28:33

CO Alarm Mistakes (Serious Safety Issue)

⏱ Mistake shown at: 29:28

Carbon monoxide safety is not optional.

Common issues include:

• No CO alarm installed

• Poor placement

• Assuming the heater is “safe enough”

▶ CO alarm discussed at 29:03
▶ Mistake highlighted at 29:28

Final Thoughts: Learn From These Autoterm Heater Mistakes

Every mistake shown in this video is something installers and suppliers see all the time — often after something has already gone wrong.

If you’re:

• Installing an Autoterm diesel heater yourself

• Fixing an existing setup

• Planning a campervan or van conversion

👉 Use this video as a checklist, not just a tutorial.

▶ Maintenance tips are covered at 30:04

Video Credit

Full credit to the YouTube creator for this excellent Autoterm heater installation guide:
🎥 https://www.youtube.com/watch?v=UndXlOJCoCw&t=1s