DIY Boat Heater Setup – Gasmate Portable Diesel Heater Boat Mod
We use this Gasmate Portable Diesel Heater in the boat cabin to stay warm on cold mornings while fishing. After a few simple mods, it’s safe, efficient, and keeps the chill out. All parts used in the setup are listed below, and you can watch the full video above to see exactly how we installed it step-by-step.
Versatile Heating for Tents and Caravans
The Gasmate Portable Diesel Heater GM20-425 isn’t just for boats—it’s also ideal for warming up tents, camper trailers, and small caravans. Designed to be set up outside your shelter, it safely delivers warm air inside via its insulated ducting, ensuring you stay cozy without the risk of carbon monoxide buildup.
Fishing in winter doesn’t mean freezing your toes off! In this video, George and I take you step-by-step through how we modified a Gasmate Portable Diesel Heater (Model GM20-425) to make it safe and effective for use on the boat. We picked ours up from BCF, and with a few simple mods, we turned it into the perfect solution for cold mornings on the water.
Why We Chose the Gasmate Diesel Heater
The Gasmate Portable Diesel Heater delivers a solid 2kW of heating power, perfect for small enclosed spaces like a cabin boat. It comes with a 4.25L fuel tank, offering up to 7 days of typical usage based on 4 hours per day at mid-range settings (power level 2–3). It’s energy-efficient, running on 12V DC, and includes 6 adjustable heat settings.
Modifying the Gasmate for Safe Boat Use
While it’s great out of the box, using any diesel heater in an enclosed area like a boat means you must safely manage exhaust fumes (carbon monoxide). Here’s what we did to make it boat-friendly:
- Exhaust System Upgrade:
We headed to Bunnings and grabbed a 25mm copper elbow and a 20mm straight steel pipe from the plumbing section. These connected perfectly to the back of the heater to redirect the exhaust. - Heat Management:
We wrapped the pipe in exhaust wrap to reduce surface heat and avoid burns or heat damage. - Safe Ventilation:
A Konnict hose rated to 60°C was used to direct the exhaust safely out of the boat cabin. - Power Setup:
We created a custom power lead using an Anderson plug to run the heater directly from the boat’s battery system. - Secure Hose Connection:
The heater’s fuel hose was connected using a solid steel barb connector (name slipped my mind, but you’ll see it in the video!).
Ready for Winter Fishing
With this setup, you can fish all winter in comfort. The heater warms the boat cabin quickly and safely, keeping morale high during those icy early starts.
👉 Watch the full video above to see exactly how we did it – from BCF to Bunnings to the back deck.
