Why does hot water demand a specialist approach?

Commercial hot water requires high temperatures (60°C minimum, 70°C+ for pasteurisation) to meet legionella compliance under Health and Safety at Work Act and L8. Standard heat pumps designed for space heating at 45-55°C cannot reliably meet these requirements without supplementary heating.

What temperature do commercial hot water heat pumps deliver?

ICG's R290 systems from Midea and Euroklimat deliver flow temperatures up to 85°C, making them fully capable of meeting commercial DHW demands and legionella compliance requirements without back-up boilers or immersion heaters.

Which sectors require high hot water demand solutions?

Hotels, guest houses, NHS hospitals, care homes, student accommodation, leisure centres, swimming pools, sports facilities, commercial kitchens, food production facilities, and laundry operations all require large volumes of hot water at temperatures high enough for legionella compliance.

Industrial machinery with multiple colorful pipes, gauges, and valves in a factory setting.

R290 Systems Delivering Up to 85°C for Domestic Hot Water, Process Heat and Legionella Compliance

Commercial Hot Water Generation with  High-Temperature Heat Pumps

Hot water is the forgotten challenge in commercial decarbonisation. Most conversations about heat pumps focus on space heating, yet in many commercial buildings, domestic hot water (DHW) represents a significant proportion of total thermal demand. Hotels, hospitals, care homes, leisure centres and student accommodation all require large volumes of hot water at temperatures high enough to satisfy legionella compliance requirements, typically 60°C at the point of use with pasteurisation cycles reaching 70°C or above.

This is where many conventional heat pump systems fall short. Standard air source units designed for space heating at 45°C to 55°C cannot reliably generate water at the temperatures required for safe commercial DHW production. At ICG Heat Pumps, we specialise in high-temperature heat pump solutions that solve this problem directly. Our R290 systems from Midea and Euroklimat deliver flow temperatures up to 85°C, making them fully capable of meeting commercial hot water demands without the need for supplementary electric immersion heaters or back-up boilers.

Domestic hot water engineering

Why Hot Water Demands a Specialist Approach

Delivering High-Demand Commercial Hot Water

Our high-temperature DHW systems are specified for estates that cannot afford a drop in performance, including commercial sites for David Lloyd and Specsavers.

Legionella Compliance

In any commercial building where water is stored, legionella risk management is a legal requirement under the Health and Safety at Work Act and the Approved Code of Practice L8. The bacteria thrive between 20°C and 45°C, which means stored hot water must be maintained at 60°C or above, and pasteurisation cycles must reach at least 70°C. A heat pump that maxes out at 55°C simply cannot meet these requirements without supplementary heating. Our systems can.

Peak Demand Profiles

Commercial hot water demand is rarely steady. A hotel experiences a sharp morning peak as guests shower simultaneously. A hospital requires consistent high-volume DHW across wards, kitchens and laundry facilities. A leisure centre with swimming pools and changing rooms generates demand patterns that bear no resemblance to an office building. Each application requires careful system sizing and buffer strategy to ensure the heat pump meets peak demand without oversizing for baseload.

Integration with Heat Pump Hot Water Cylinders

The performance of a hot water heat pump system depends heavily on the cylinder and storage configuration. We provide complete system design support, including cylinder selection, primary circuit design, thermostatic mixing valve specification and recirculation strategy. Whether you are using a dedicated DHW heat pump or generating hot water as a secondary function of your space heating plant, we design the system to work as an integrated whole.

Hot water engineering

Our Hot Water Solutions

Outdoor industrial HVAC unit connected to insulated pipes near a building with windows.

Dedicated DHW Heat Pumps

For buildings where hot water is the primary thermal load, such as hotels, care homes and student accommodation, we can specify dedicated R290 heat pumps operating at 70°C to 85°C flow temperature. The Euroklimat Thermion HT range is purpose-built for this application, delivering high-temperature hot water with class-leading COP at elevated output temperatures.

Two ICG engineers wearing helmets and reflective vests inspecting large industrial HVAC units at night.

Combined Space Heating and DHW

Many commercial buildings require both space heating and domestic hot water from a single plant. We design dual-circuit systems using high-temperature heat pumps that serve the space heating circuit at one temperature and pre-heat or directly generate DHW at another. This avoids the cost and complexity of separate heating and hot water plant, while ensuring both demands are met reliably.

Multiple black Midea HVAC units installed outdoors beside a brick building and a fence, with insulated pipes running along the ground.

Heat Pump Hot Water Cylinder Specification

We work with leading UK cylinder manufacturers to specify hot water storage that is optimised for heat pump operation. Unlike conventional boiler cylinders, heat pump cylinders require larger coil surface areas and careful stratification management to maintain COP. We specify the right cylinder for the job, not just the cheapest one that fits the plant room.

High-demand sectors

Sectors with High Hot Water Demand

Our commercial hot water solutions are deployed across hotels, guest houses and serviced apartments, NHS hospitals and primary care facilities, care homes and sheltered housing, student accommodation and university halls, leisure centres, swimming pools and sports facilities, commercial kitchens and food production facilities, and laundry and cleaning operations.

Low-angle view of three modern skyscrapers with glass and metal facades against a gray sky.

Office developments

Empty urban plaza with modern glass office buildings reflecting surrounding structures on a sunny day.

Commercial and mixed-use developments

Aerial view of numerous green garbage trucks parked in organized rows next to a large warehouse building.

Logistics & warehousing

Interior view of a modern shopping mall with a large curved glass ceiling, escalators, and wooden flooring.

Retail parks and shopping centres

Modern hotel room with a double bed, round white table with laptop, curved sofa with colorful cushions, wooden floor, and large window with beige curtains.

Hotels, leisure and hospitality

William R. Samford Hall, a historic red brick building with a clock tower, on Auburn University campus under clear blue sky.

Education & specialist infrastructure

Testimonials

Reliable High-Demand Performance

"Trevor attended site to go through the ASHPs’ operation, how the units work and what heating outputs they can provide, we’re operating with low temperatures ( 35°C F / 30°C R) however Trevor explained that the units can provide much higher heating outputs if required. Trevor was also very thorough when explaining the system and how to use the master controller, taking his time to answer fully any questions asked by the school’s estates team."

Ross Mcintosh, T Clarke

Commercial Hot Water Generation with High-Temperature Heat Pumps