Efficient Heating For Large Spaces: LPHW Unit Heaters
Reventon S Series LPHW Unit Heater
Apen AX LPHW Unit Heater
Reventon S Series LPHW Unit Heater
When it comes to heating large commercial or industrial buildings — such as warehouses, workshops, or sports halls — few systems are as effective and energy-efficient as Low Pressure Hot Water (LPHW) Unit Heaters.
These powerful systems use hot water from a central heat source — such as a boiler or a heat pump — to deliver consistent, comfortable warmth. Hot water circulates through a finned coil inside the unit, while a fan draws in ambient air and blows it over the heated surface. The result is a strong, even flow of warm air that quickly raises temperatures in large or open spaces.
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Because they rely on water rather than direct electrical resistance or gas combustion, LPHW unit heaters offer excellent flexibility and efficiency. They can be connected to:
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Gas or oil boilers, for traditional high-temperature water systems
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Air-source or ground-source heat pumps, for low-temperature renewable heating
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Hybrid systems, combining both for optimal year-round performance
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This adaptability makes LPHW unit heaters an excellent choice for energy-efficient industrial heating and future-ready HVAC systems.
Apen AX LPHW Unit Heater
The Apen AX range is designed for high-performance heating and cooling. With outputs from 7 kW up to 125 kW, these units are suitable for anything from small workshops to large warehouses.
Key features:
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Compatible with boiler and heat pump systems
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Horizontal or vertical mounting options for flexible installation
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Optional EC fan motors for quieter, more efficient operation
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Dual-mode capability, allowing heating or cooling depending on your system design
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Modern, compact styling suitable for commercial and retail environments
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Thanks to its wide power range and advanced fan technology, the Apen AX delivers energy-efficient warm air heatingthat integrates seamlessly with both traditional boilers and modern heat pumps.
Reventon S Series LPHW Unit Heater
The Reventon S Series (including the S-3S range) is engineered for tough, industrial environments where reliability is key. Offering 2 kW to 66 kW of output, these units provide dependable heating for warehouses, factories, and production areas.
​Highlights:
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Works with LPHW boiler or heat pump systems
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Durable galvanised steel casing with a powder-coated finish
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3-speed fan motor and IP54 protection for demanding conditions
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Multiple coil configurations for different water temperatures and flow rates
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Flexible wall or ceiling mounting options
Built to last, the Reventon S Series combines robust construction with efficient hot water heating, making it a cost-effective choice for industrial and commercial applications.
The Smart Choice for Efficient Industrial Heating
Whether powered by a gas boiler or a renewable heat pump, LPHW unit heaters provide an efficient and future-proof way to heat large spaces. They integrate easily into central hot-water systems, reduce running costs, and offer fast, controllable heating for year-round comfort.
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Both the Apen AX and Reventon S Series — available from Hadar Industries — are excellent examples of performance, flexibility, and reliability in modern industrial heating.
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If you’re looking to upgrade your factory, warehouse, or commercial space heating system, LPHW unit heaters offer the perfect balance of efficiency, power, and long-term value.
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