When it comes to heating large industrial buildings such as warehouses, factories and workshops, warm air unit heaters continue to provide the most practical and cost-effective solution for the vast majority of sites across the UK. Despite the push towards greener alternatives, modern warm air heaters offer a compelling combination of efficiency, flexibility and reliability that is difficult to match.

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Why Warm Air Unit Heaters Remain the Smart Choice

 

Warm air unit heaters deliver fast, even heat distribution across large open spaces. Suspended from the ceiling or wall-mounted to save floor space, they can be zoned to heat different areas independently and controlled with modern thermostats and building management systems. Available in gas-fired, oil-fired, LPHW and electric configurations, they suit virtually every building type and fuel supply. Today's high-efficiency models achieve seasonal efficiencies of 90% and above with modulating burners that automatically match output to demand, reducing fuel waste and lowering running costs.

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The Reality of Green Alternatives for Industrial Buildings

 

Heat pumps and electric heating can offer lower carbon emissions under the right conditions, but for most large industrial spaces they come with significant challenges: high capital cost (several times that of gas or oil-fired systems), limited electrical capacity in most existing buildings (costly transformer upgrades and long waits for grid reinforcement), long payback periods extending beyond a decade, and reduced efficiency in poorly insulated buildings with high ceilings and frequent door openings. For many sites, upgrading to modern high-efficiency warm air unit heaters offers a more sensible balance between cost, performance and environmental improvement.

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Apen Gas-Fired Warm Air Unit Heaters

 

The Apen range of gas-fired warm air unit heaters is engineered to provide exceptional performance and energy efficiency across a wide variety of industrial and commercial environments. The range includes the Apen LRN and Apen LKN models, each offering high seasonal efficiency, modulating burners and low NOx performance.

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• High seasonal efficiency: Up to and exceeding 90%, reducing fuel consumption and running costs

• Modulating burners: Automatically adjust output to match demand, reducing fuel waste

• Compact wall or ceiling mounted design: Saves valuable floor space in warehouses, factories and workshops

• Low NOx emissions: Improved environmental performance without sacrificing heat output

• Smart control compatible: Works with thermostats and building management systems​​

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Hadar Fornax Oil-Fired Warm Air Unit Heater

 

For sites without access to mains gas, the Hadar Fornax oil-fired warm air unit heater delivers reliable, efficient heating performance. Available from 30 to 200 kW with a 304 stainless steel heat exchanger, the Fornax is built for demanding industrial environments and is compatible with both traditional heating oil and HVO renewable fuel.

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• 304 stainless steel heat exchanger: Robust construction for long life in demanding environments

• HVO compatible: Switch to renewable HVO fuel for up to 90% lower carbon emissions

• Rapid warm-up: 35 second ignition on oil, 28 seconds on HVO

• Off-grid ready: Ideal for warehouses, workshops and agricultural buildings without mains gas

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A Practical Path Towards Lower Carbon Heating

 

For most facilities, upgrading to modern high-efficiency warm air unit heaters is the most sensible route to lower fuel consumption and emissions. Off-grid sites can switch to HVO in a Hadar Fornax for up to 90% lower carbon as a drop-in fuel change. Sites with a central boiler or heat pump can use LPHW unit heaters, such as the Apen AX or Reventon S-3S, that are already heat pump ready. And the Apen AquaPump hybrid heat pump offers a phased pathway to lower carbon by combining a heat pump with a condensing gas boiler. Contact Hadar Industries today for a free site survey.