Heat Recovery Systems for Oil-free Compressors

Turn waste heat to your advantage

Heat Recovery Save Money and reduce your

ASK heat recovery solutions help convert wasted compressor heat into useful energy for industrial processes, hot water generation, and facility heating applications. By recovering and reusing thermal energy that would otherwise be lost, businesses can significantly improve energy efficiency, lower operating costs, and reduce environmental impact.

Why heat Recovery

It is a well-established thermodynamic principle that approximately 94% of the energy used to operate a compressor is converted into heat. Without a heat recovery system, this valuable energy is simply released into the atmosphere and lost.

The heat generated during compression is already paid for as part of the energy input, yet additional costs are incurred to remove it using cooling fans or water-cooling systems. Meanwhile, many industries continue to spend significant energy and money generating hot process water, space heating, or preheated water for steam production.

Since compressed air systems account for around 10% of total industrial electricity consumption—and energy represents the largest lifecycle cost of a compressor—it is both logical and economical to recover this waste heat wherever possible. Doing so reduces operating costs, improves overall system efficiency, and significantly lowers environmental impact.

Different Oil-free Heat Recovery Systems

The ASK Ultima compressor range offers flexible heat recovery solutions tailored to different customer requirements and installation setups. Water-cooled models can be supplied with basic preparation for external heat recovery, advanced Heat Recovery+ control for managing cooling water outlet temperature, or the fully integrated E-max turnkey system that includes all essential components for a complete heat recovery solution.

A unique advantage of the Ultima range is its integrated heat recovery option for air-cooled models. Ultima is the first and only air-cooled oil-free compressor on the market offering optional heat recovery, capable of delivering usable hot water temperatures up to 85°C. This fully integrated, turnkey solution requires no additional footprint or complex installation and provides significant annual energy savings while improving overall system efficiency.

So how much can you actually save?

Heat recovery from ASK compressors can typically recover a large portion of the energy used during compression, since up to 94% of input energy is converted into heat. In practical applications, this means a significant share of that energy can be reused for useful purposes such as space heating, hot water generation, or process heating.

Depending on system design, operating hours, and application demand, users can achieve substantial reductions in energy costs and noticeable decreases in CO₂ emissions. In many industrial installations, this results in a short payback period and long-term lifecycle savings, making heat recovery one of the most effective ways to improve overall compressed air system efficiency.

D-Series Heat Recovery Capability

The ASK D-Series water-cooled compressors (37 kW to 315 kW), available in both fixed speed and regulated speed versions, can be equipped with preparation for external heat recovery systems. This enables the recovery of waste heat to produce hot water at temperatures of up to 75°C or even 90°C, depending on the model.

In addition, D-Series models up to 200 kW are compatible with the E-max turnkey heat recovery solution, providing a fully integrated and efficient system for maximizing energy recovery, reducing operating costs, and improving overall system sustainability.

E-Max a turnkey heat recovery system for oil-free compressors

High-efficiency heat recovery heat exchanger for heating usable water
Backup heat exchanger to maintain safe compressor cooling when heat demand is low
Speed-controlled pump for precise regulation of cooling water temperature before heat exchange
Intuitive color touch screen controller for easy system monitoring and operation
Real-time visualization of current and total recovered heat for performance tracking

U-Cooler/E-Cooler - a Recovery Capability

The ASK Ultima system features a highly efficient V-shaped cooling module designed for reliable and effective waste heat removal from the compressor cooling cycle. This advanced design ensures stable thermal management and optimal operating conditions even under demanding load scenarios.

The complete integrated package includes the cooling module, pump station, and intelligent control system, all fully incorporated within the compressor unit. This turnkey solution offers easy installation, simplified operation, and virtually maintenance-free performance, while maximizing energy efficiency and system reliability.