Adding Diesel Heater To Garage Shop Via Foundation Vent | #34

It is winter. My garage is uninsulated. It is 40 degrees inside. Wood glue stops working at 50 degrees. My fingers stop working at 45. I needed heat.

Electric heaters are expensive to run (and require 220V wiring I don't have). Propane heaters dump moisture into the air (rusting my tools). Enter the Chinese Diesel Heater (CDH). These are knock-offs of expensive German truck heaters (Webasto/Eberspacher). You can buy a clear 5KW or 8KW kit on Amazon for $120.

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How It Works

It's a miniature jet engine.

1. It pumps diesel fuel into a combustion chamber.
2. It lights it with a glow plug.
3. The box gets hot.
4. A fan blows air over the outside of the hot box (heat exchanger) and into your room.
5. Critically: The exhaust gas (Carbon Monoxide) is blown outside via a separate pipe. The room air and the combustion air never mix. This means dry, safe heat.

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Material & Tools

• Diesel Heater Kit: Includes heater, pump, tank, and controller.
• 12V Power Supply: These run on 12V DC (car voltage). You need a AC-to-DC converter (like a 20A LED power supply) to run it from a wall outlet.
• Exhaust Thimble: A metal pass-through to safely route the hot exhaust pipe through the wall.

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The Installation Process

Step 1: Mounting Location

I chose a corner near the garage door. I mounted the heater unit on a plywood shelf on the wall, high up (heat rises, but I wanted the exhaust run to be short).

Step 2: The Exhaust (Safety Critical)

I drilled a 1-inch hole through the wooden header above the foundation vent.

• Insulation: The exhaust pipe gets to 500 degrees. It will burn wood. I wrapped the pipe in fiberglass exhaust wrap (header wrap) and used a double-walled metal thimble.
• Muffler: I attached the included muffler on the outside of the building. It sounds like a quiet whoosh, not a tractor.

Step 3: Fuel Supply

The kit comes with a 10L plastic tank. I mounted this on the wall above the heater.

• The Pump: The fuel pump makes a "tick-tick-tick" sound. It is annoying. I suspended the pump with zip ties and rubber bands so it doesn't transmit the vibration to the wall. This is the "Silent Pump Mod."

Step 4: Power

I wired the 12V power supply.

• Startup: On startup, the heater draws 10-12 Amps to heat the glow plug. Your power supply MUST handle this surge. A 5A laptop brick will not work. Get a 20A or 30A supply.

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Performance

I verified the exhaust was sealed. I hit the "Health" button on the remote. After 3 minutes of startup cycle... HEAT. Serious heat. The output air is 180 degrees. Within 30 minutes, my 2-car garage went from 40F to 65F. Within an hour, it was 72F and I was in a t-shirt.

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Fuel Consumption

It burns about 0.1 liters per hour on low. A gallon of diesel lasts me 2 or 3 heavy weekends of woodworking. Compared to electric heat, it is incredibly cheap.

Conclusion

This is the best upgrade for year-round woodworking. No more freezing glue. No more numb fingers. Just a warm, dry shop.