Hi everyone, Barnaby here from Electric Car Converts.
Heating and air conditioning are some of the trickiest parts of EV conversions, the hard bits no one really talks about. So in this video/blog, I’ll show you how we’ve solved it on the biggest Land Rover we’ve ever built: a high-capacity Defender 130 Puma. It’s huge, it’s tough, and now it’s running proper high-voltage HVAC that feels totally OEM.
Electric Land Rover Air Con: How It Works
This 130 originally came with a diesel-powered air conditioning system, which included an evaporator located inside the dashboard and a standard blower system. We retain as much of the original equipment as possible, ensuring that all vents, switches, and controls operate identically to the factory setup.
Instead of a belt-driven compressor, we now run a 350-volt electric compressor. It sits neatly under the bonnet, a silver cylinder with a hot line on one side and a cold line on the other.
The condenser was the tricky bit. On old Puma Defenders, the condenser often sits up front, blowing hot air straight over your cooling pack. Not good; after five minutes of air conditioning, the motor and battery radiators suddenly saw 90°C air, which triggered all the fans to kick in.
Now, we mount the condenser away from the EV cooling system, tucked in where the fuel tank used to be. It’s ducted, out of harm’s way, and it pushes heat down and out instead of into the motor. Much better.
Inside, it’s seamless. You turn the key, press the original air con button, and cool air flows through the stock vents: feet, screen, dash, wherever you want it. On a 34°C day, we saw vent temps drop to 16°C within seconds.
High-Voltage Heating for Electric Defenders
Heating is where the most recent changes have occurred.
We used to use PTC heaters, essentially large resistors that got hot, like a giant hair dryer. They worked, but mounting them inside the dashboard was a messy process.
Now we’ve switched to high-voltage water heating. We’re using a 7kW BMW i4 water heater, plumbed into a dedicated hot water circuit. It heats the coolant to 80–90°C, which then flows through the original heater matrix.
That means all the original heater controls and vents work exactly as they should. You pull a lever, the Bowden cables move, and the airflow changes. The only difference is that the heat comes from an electric water heater, rather than an engine.
On this 130, we were running the heater at just 40% power, and within seconds, the vent temps hit 49°C. Pipes too hot to touch. In winter, it’ll be instant heat with no waiting for an engine to warm up.
EV Battery Preconditioning with Heating and Cooling
Here’s the clever bit: because the air conditioning and heating systems are high-voltage, we can also use them to condition the battery pack.
Sending a car to Dubai? We can use the air conditioning circuit to actively cool the battery down.
Sending one to Scandinavia? We can utilise the hot water circuit to preheat the pack before charging, making the process faster and more efficient.
We haven’t had to use this yet in the UK or US, but the option’s there when needed.
Why Upgrade to High-Voltage HVAC in Electric Land Rovers
So now every one of our conversions comes with high-voltage heating as standard. Air con is optional, depending on what your base car has. If the evaporator’s already there, it’s simpler and cheaper. If not, we can fit a new system.
The point is that you get a proper OEM-feel HVAC system. Cold air, hot air, all on the original switches, with no hacked-in panels. It makes these old Land Rovers feel properly modern inside.
Underneath, it’s still the same recipe: a 55kWh Fellten battery up front with a Tesla Model 3 motor underneath driving the propshafts. With this HVAC system, the driving experience moves from “classic utility” to being seriously usable every day.
Thanks for reading, and if you want to feel freezing air conditioning or boiling heat for yourself, come down and see one of the cars in person.
See you at the next one.