In our latest update, the spotlight remains on the Land Rover Defender electric air conditioning project. Following the initial introduction, this phase looks more into the development process, with the focus on reworking the heating system and adding air conditioning to the classic Land Rover Defender, we now enter into testing.

The blower unit is now fully installed and wired, so how does it all work? Hot water flows through the heater matrix, controlled by a servo-operated water valve that switches off the heat feed when the AC is activated. A servo flap ensures precise temperature blending, with an ECU that oversees all heating and AC functions, similar to our units that are used in Porsche 911 projects but with modified software. The refrigerant lines have charge ports for gas filling, and the compressor is mounted under the vehicle.

Historically, Land Rover Defenders had units that fitted awkwardly under the dash, compromising footwell space and seeming somewhat like an afterthought. We’ve created a plug-and-play system, so it seamlessly integrates alongside the original heater box, ensuring a tidy finish without taking up valuable space in the cabin.

Inside the Defender, the goal is to produce a system that looks factory-installed. The dashboard has been subtly reworked, incorporating adjustable vents where there used to be just a cigarette lighter and a rear wiper switch. These vents, which can be directed in any direction, are part of a prototype control panel that will eventually reflect Land Rover’s design language. Additionally, the footwell vents have been modified to be adjustable, improving passenger comfort.

A significant challenge in retrofitting AC into the Defender is avoiding condensation on the dash panel, which also serves as the main firewall for the engine bay. To tackle this, we have engineered a system of internal compartments within the dashboard. This system directs airflow specifically to the vents, minimising exposure to hot surfaces. Foam parts further insulate these compartments, ensuring that once the original parts are reinstalled, the modifications are invisible.

Despite their small size, these vents are highly efficient. in the video, a quick test is done which shows air speeds of up to 30 mph being recorded from the vents. And after a quick drive, outlet temperatures reached the freezing point, producing temperatures of 0°C (32°F!)

 

This update marks significant progress in the Land Rover Defender heating and air conditioning project. As the system nears production, we will post more about the finished product.

For continued updates on this and other exciting projects, including work on Porsche, Alfa Romeo, and various EV conversions, stay tuned to the Classic Retrofit blog and follow us on social media.