Draper 230V Far Infrared Diesel Heater with Flue Kit, 40,000 BTU/11.6kW

The Draper DSH400/FLUE Far Infrared Diesel Heater is the most compact and economical model in Draper's far infrared flue heater range — purpose-built for single-bay garages, small workshops and compact commercial spaces of up to approximately 66m². Producing 40,000 BTU (11.6kW) of evenly distributed far infrared warmth, it draws just 40W of electricity and consumes as little as 0.9L/hr of diesel — the lowest running costs of any heater in the DSH flue range.

Like both larger models in the range, the DSH400/FLUE comes with a supplied flue kit that enables use in enclosed indoor spaces without ventilation — a capability unique across the entire Draper DSH heater lineup. Remote control, a digital thermostat and a 24-hour programmable timer provide full automated control, while the far infrared technology delivers quiet, odour-free warmth spread evenly throughout the space.

For single-bay garages, compact workshops and smaller enclosed commercial premises where an efficient permanent heating solution is needed, the DSH400/FLUE offers everything the larger flue models deliver — scaled to the right size.

Key Features

Far Infrared Heat — Even Warmth in All Directions

The DSH400/FLUE's far infrared radiant technology distributes heat evenly throughout the space in all directions, rather than directing a stream of warm air from a single point. Occupants, surfaces and objects throughout the room absorb warmth naturally and consistently — no cold spots, no draughts, no uneven heating.

Flue Kit Included — Suitable for Enclosed Indoor Use

The supplied flue kit vents combustion gases externally, making the DSH400/FLUE suitable for enclosed indoor spaces that are not well-ventilated — the same unique capability shared by the DSH515/FLUE and DSH675/FLUE, and found nowhere else in the Draper range. For small sealed garages and compact enclosed workshops where combustion heaters would otherwise be unsafe, this flue kit is the practical enabler of cost-effective diesel heating. The flue must always be connected in non-ventilated indoor spaces; without it, operate only in well-ventilated areas.

Remote Control

The remote control puts full operation — temperature, timer, on/off — in your hand from anywhere in the space. No need to approach the unit, making it particularly convenient for permanently installed or wall-adjacent applications.

Digital Thermostat with LED Control Panel

The digital thermostat and LED control panel provide precise temperature management at the unit. Set your target and the heater maintains it automatically, cycling fuel consumption as needed — maximising economy over long periods of use.

24-Hour Programmable Timer

The 24-hour timer automates the heating schedule around your day — starting the heater before you arrive, shutting it down when you leave, without any manual intervention. For a regularly used workshop or garage, this hands-off control reduces fuel waste and ensures the space is always warm when you need it.

The Lowest Running Costs in the Flue Range — 40W & 0.9L/hr

At just 40W electrical draw and 0.9L/hr diesel consumption, the DSH400/FLUE is the most economical heater in Draper's far infrared flue range. Compared to even modestly-sized electric heaters, the fuel cost saving over a typical heating season is substantial — and the 40W electrical draw adds virtually nothing to an electricity bill.

Very Low Noise

Far infrared heating requires no high-powered fan, and the DSH400/FLUE operates at very low noise levels — notably quieter than any forced-air model in the Draper range. Ideal for workshops where concentration matters, or compact commercial spaces shared with customers or colleagues.

Virtually Odourless

The clean indirect combustion design produces minimal odour — a meaningful advantage in the smaller, more enclosed spaces this model is designed for, where fumes from less refined combustion would be more noticeable.

Compact and Wheeled

At 40kg and with a 710mm x 320mm footprint, the DSH400/FLUE is the most compact of the three far infrared flue models — easier to manoeuvre in tight spaces and less intrusive in a small workshop or garage. Fitted wheels allow repositioning without lifting.

Diesel and Kerosene Compatible

Operates on both diesel and kerosene from the 25-litre tank, providing flexibility on fuel choice.

Specification

Two Ways to Use the DSH400/FLUE

Without Flue — Well-Ventilated Spaces In garages, barns, workshops, warehouses and marquees with adequate natural ventilation, the DSH400/FLUE operates as a portable far infrared heater without flue connection — safely and effectively, as with other well-ventilated combustion heaters.

With Flue — Enclosed Indoor Spaces With the supplied flue kit connected and venting externally, the DSH400/FLUE becomes suitable for enclosed indoor spaces without ventilation — opening up single-bay sealed garages, compact workshops and small enclosed commercial units to efficient, controllable diesel heating.

Important: The flue kit must always be installed and in use before operating in any enclosed or poorly ventilated space. Never use in an enclosed space without the flue properly connected.

Where to Use the Draper DSH400/FLUE

Without flue (well-ventilated):

• Single-bay garages and small workshops with natural airflow
• Small agricultural outbuildings and storage buildings
• Compact well-ventilated commercial or light industrial spaces
• Small marquees and covered event spaces

With flue installed (enclosed indoor spaces):

• Sealed single-bay garages
• Small enclosed workshops
• Compact commercial premises and studio spaces
• Small indoor agricultural buildings without natural ventilation
• Permanent installations in enclosed spaces up to 66m²

Choosing Across the Draper Far Infrared Flue Range

All three models in the Draper far infrared flue range share the same remote control, digital thermostat, 24-hour timer and flue kit — the difference is the size of space each is built to heat:

Match the model to your floor area and the choice is straightforward. The DSH400/FLUE is the lightest, lowest-consumption and most affordable to run — built specifically for spaces up to 66m².

Why Choose the Draper DSH400/FLUE?

For owners of a single-bay garage, a compact workshop or a small enclosed commercial space, the DSH400/FLUE resolves the central heating challenge of sealed indoor spaces: how to heat them efficiently with a combustion heater when there's no ventilation. The supplied flue kit is the answer — and with it, diesel heating becomes accessible in spaces where only electric heating was previously practical.

The DSH400/FLUE doesn't scale down the features to match its smaller size. Remote control, digital thermostat and 24-hour timer are all present — giving the same quality of control and automation as the larger models, from the most compact and economical package in the range. At 0.9L/hr and 40W, its running costs are genuinely low, and its near-silent, odour-free operation makes it pleasant to work alongside day after day.

For the right space, this is the most cost-effective far infrared flue heater Draper makes.

Frequently Asked Questions

Must I use the flue kit? The flue kit must be installed and operational whenever the heater is used in an enclosed space that is not well-ventilated. In well-ventilated spaces — garages, workshops and barns with adequate natural airflow — it can be operated without the flue. Never use in an enclosed, airtight or poorly ventilated space without the flue properly connected.

How long will a full tank last? At 0.9L/hr fuel consumption, the 25-litre tank provides approximately 27 hours of operation at full output — the longest tank runtime of the three far infrared flue models. With thermostatic cycling, real-world runtime extends further in normal use.

How does the DSH400/FLUE compare to the DSH515/FLUE? The DSH400/FLUE heats spaces up to 66m² at 0.9L/hr from a 25-litre tank. The DSH515/FLUE heats spaces up to 85m² at 1.2L/hr from a 30-litre tank. Both include the same remote control, thermostat, timer and flue kit. Choose the DSH400/FLUE for spaces up to 66m²; step up to the DSH515/FLUE for spaces up to 85m².

Can it run on kerosene? Yes — the DSH400/FLUE is compatible with both diesel and kerosene.

How large a space will it heat? The DSH400/FLUE is designed for spaces of approximately 66m² — equivalent to a single-bay garage or workshop of around 8m x 8m, or a compact commercial unit of similar area.

How does the 40W electrical draw compare to electric heaters? A 40W draw is negligible — roughly equivalent to an LED bulb. All meaningful heat output comes from diesel combustion at 0.9L/hr. For comparison, a 3kW electric fan heater draws 3,000W continuously. The DSH400/FLUE produces nearly four times the heat output of that electric heater at a fraction of the electrical cost.

Is this heater suitable for a sealed garage? Yes — with the flue kit properly installed and venting combustion gases externally, the DSH400/FLUE is suitable for sealed, enclosed garages without ventilation. It is the only type of combustion heater in the Draper range that can be used this way.