Heat Networks

Modutherm's comprehensive range of heat interface units (HIUs), heat stations, and commercial heat pumps are designed for fourth and fifth generation district heating networks. Our heat pump optimised MTA Plus Twin passed the 2023 BESA HIU Test, with 7 Best Practices Achieved. From compact twin-plate HIUs for apartment buildings to ambient loop heat stations and commercial air source heat pumps, our heat network solutions deliver exceptional efficiency for multi-dwelling residential developments, social housing, and commercial properties across the UK.

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What are the benefits of HIUs?

Heat Interface Units (HIUs) are the smart solution for modern district heating and communal heating systems, delivering exceptional value for developers, residents, and building managers in apartment blocks and multi-dwelling properties.

Space-saving and cost-effective for multi-dwelling developments

HIUs eliminate individual boilers in each flat, reducing capital costs and freeing up valuable space. With no gas supply infrastructure or flues required, construction is simpler and more cost-effective for apartment blocks and residential developments. At just 600 x 500 x 312mm, our MTA HIUs fit neatly into a cupboard. Centralised heating means one efficient plant room instead of servicing hundreds of individual boilers—ideal for social housing, student accommodation, and new build projects.

Instant comfort with instantaneous hot water

Residents enjoy instant domestic hot water (DHW) without waiting, plus precise space heating control for underfloor heating (30-45°C) or radiators (45-80°C). Our twin plate HIU design operates quietly with no combustion in dwellings—eliminating gas pipes and carbon monoxide risks. Advanced diagnostics with remote monitoring enable quick issue resolution, often without site visits.

Energy efficiency and heat pump optimised performance

District heating networks with HIUs enable efficient heat generation from combined heat and power (CHP), renewable sources, or heat recovery systems. Modern HIUs are specifically heat pump optimised for low temperature heat networks, ensuring exceptional return temperature performance for maximum efficiency and reduced operational costs. Our MTA Plus achieved the lowest VWART (Volume Weighted Average Return Temperature) scores in BESA testing—26°C (high) and 24°C (low)—confirming it as the UK's best performing heat interface unit for fourth-generation heat networks. As the grid transitions to renewable energy, your entire building benefits automatically.

Smart metering and heat network management

Integrated heat metering ensures residents pay only for the energy they use, promoting fairness and energy-conscious behaviour in apartment complexes. Optional remote connectivity and building management system (BMS) integration provide real-time performance data for continuous heat network optimisation whilst reducing maintenance visits—perfect for managing communal heating across residential buildings.

Heat Pumps

Heat pumps provide energy-efficient heating, cooling, and domestic hot water by extracting renewable heat from the air, ground, or water. Modutherm's comprehensive range includes commercial air source heat pumps (Hybrox and AW290, 10-100kW heating, 8.6-85kW cooling), brine/water source heat pumps (Alterra WZSV and PWZSV, 5.95-17.2kW), and exhaust air heat pump water heaters (Juniper HP Plus, 200-300L). These systems are suitable for apartment buildings, hotels, schools, commercial properties, and heat network applications across the UK.

Air Source Heat Pumps

An air source heat pump (ASHP) provides energy-efficient space heating, cooling, and domestic hot water by extracting renewable heat from outdoor air. Modutherm's commercial air source heat pumps include the Hybrox and AW290 series, with heating outputs from 10-100kW and cooling capacities from 8.6-85kW. With A+++ energy efficiency ratings, these R290 heat pumps are ideal for apartment buildings, hotels, schools, and commercial heat network applications.

Brine/Water Source Heat Pumps

A brine/water source heat pump (also known as a ground source heat pump or geothermal heat pump) provides energy-efficient space heating, cooling, and domestic hot water by extracting renewable heat from the ground via geothermal probes, ground collectors, or ambient loop heat networks. Modutherm's Alterra brine/water heat pumps include the WZSV and PWZSV series, with heating outputs from 5.95-17.2kW. Achieving COPs of up to 4.92 and A+++ energy efficiency ratings, these compact heat stations include integrated 180-litre stainless steel domestic hot water cylinders. Ideal for apartment buildings, residential properties, and heat network applications where space is at a premium, they deliver exceptional efficiency from ground-sourced renewable energy.

Exhaust Air Heat Pump Water Heater

An exhaust air heat pump water heater provides energy-efficient domestic hot water by extracting heat from the air rather than generating it directly with electricity. The Juniper HP Plus is an exhaust air heat pump water heater that achieves a COP of up to 4.09, producing over four times more heat energy than the electricity it consumes – earning an A++ energy efficiency rating.

What are the benefits of air source heat pumps?

Air source heat pumps are the versatile, energy-efficient solution for modern heating and cooling systems, delivering exceptional performance and low running costs for commercial properties, apartment blocks, and new build developments.

Exceptional energy
efficiency and cost savings

Air source heat pumps deliver outstanding energy efficiency, significantly reducing heating costs compared to traditional gas boilers or electric heating systems. The Modutherm range achieves COPs up to 5.55 and A+++ energy efficiency ratings, meaning they produce over five times more heat energy than the electricity they consume. The Hybrox series (10-18kW) achieves COP up to 5.55 at A7/W35 conditions, whilst the AW290 range (35-100kW) delivers COP up to 4.4. This exceptional efficiency translates directly to lower energy bills and reduced carbon emissions. Air source heat pumps extract renewable heat from outdoor air, even at temperatures as low as -22°C, making them reliable year-round heating solutions for UK climates. With natural R290 refrigerant that has a Global Warming Potential of just 3 and zero Ozone Depletion Potential, these systems offer both economic and environmental benefits that align with net-zero carbon targets and increasingly stringent building regulations.

Versatile heating and cooling capability

Air source heat pumps provide both heating and cooling from a single system, offering year-round climate control and exceptional value for money. The AW290 range delivers 35-100kW heating capacity and 8.6-85kW cooling capacity, making it ideal for commercial applications including offices, hotels, schools, and leisure facilities. This dual functionality eliminates the need for separate heating and cooling systems, reducing capital costs, installation complexity, and ongoing maintenance requirements. The systems can provide space heating via radiators or underfloor heating, domestic hot water production, and air conditioning during summer months. With flow temperatures up to 78°C at -22°C outdoor temperatures (Hybrox), these heat pumps work effectively with existing radiator systems in retrofit applications, whilst also being optimised for low-temperature systems in new builds. The ability to cascade multiple units allows heating capacities up to 1,600kW, making air source heat pumps suitable for large-scale commercial developments.

Future-proof technology
for decarbonisation

Air source heat pumps are at the forefront of the UK's transition away from fossil fuels, fully aligned with the Future Homes Standard and net-zero carbon commitments. Unlike gas boilers that burn fossil fuels, air source heat pumps extract renewable heat from the outdoor air and use electricity to transfer that heat into buildings. When powered by renewable electricity from solar panels or green tariffs, they offer a truly zero-carbon heating solution. The Modutherm range uses natural R290 refrigerant with a Global Warming Potential (GWP) of just 3, compared to thousands for synthetic refrigerants or the carbon emissions from gas combustion. This makes them one of the most environmentally responsible heating technologies available. With no combustion, no flue requirements, and no gas safety concerns, air source heat pumps eliminate carbon monoxide risks and reduce maintenance demands. As grid electricity continues to decarbonise, the environmental performance of heat pumps improves automatically, providing long-term sustainability without equipment replacement.

Scalable solutions for any project size

Air source heat pumps offer flexible, scalable solutions suitable for single dwellings through to large commercial developments. The Hybrox range (10-18kW) is ideal for individual apartments, houses, and small commercial properties, whilst the AW290 series (35-100kW, expanding to 100kW in Q3 2026) serves larger applications. Multiple units can be cascaded together to achieve heating capacities up to 1,600kW, making them suitable for hotels, apartment blocks, schools, leisure centres, and industrial facilities. This scalability provides design flexibility and allows systems to be sized precisely to match building loads, avoiding the inefficiencies of oversized equipment. Air source heat pumps can be installed as standalone systems or integrated into heat networks, combined with buffer vessels for hydraulic separation, or paired with thermal stores for domestic hot water production. The compact outdoor units require minimal space and can be wall-mounted or floor-standing, making them suitable for properties with limited plant room space or restricted external areas.

Smart controls and system integration

Modutherm's air source heat pumps feature advanced controls and connectivity options that maximise efficiency, comfort, and ease of management. Smart controls optimise operation based on outdoor temperatures, occupancy patterns, and electricity tariffs, reducing running costs whilst maintaining precise indoor comfort levels. The systems integrate seamlessly with building management systems (BMS) via Modbus connectivity, enabling remote monitoring, performance analytics, and fault diagnostics. This connectivity is particularly valuable for commercial properties, housing associations, and multi-dwelling buildings where centralised management reduces operational overhead. Weather compensation adjusts output automatically based on outdoor conditions, eliminating temperature overshoots and improving comfort whilst reducing energy waste. The Modutherm range is compatible with smart home systems, time-of-use electricity tariffs, and demand-side response programmes, allowing operation to be scheduled when grid electricity is cheapest or greenest. When paired with solar PV systems, air source heat pumps can be configured to operate primarily when renewable electricity is being generated, further reducing energy costs and carbon emissions.

Boilers

Modutherm offers a comprehensive range of commercial boilers including wall hung and floor standing gas condensing boilers (32-1156kW) and electric boilers (36-504kW). Our Genesis range features stainless steel heat exchangers, modular configurations, and high-efficiency performance for commercial heating applications. The Genesis Eco electric boiler range delivers 99.9% efficiency for zero-carbon heating solutions. Suitable for schools, hotels, care facilities, apartment buildings, and commercial properties, Modutherm boilers provide reliable, powerful heating for new builds, refurbishments, and hybrid heating systems across the UK.

Condensing Boilers

Modutherm's Genesis condensing boiler range includes wall mounted and floor standing models with outputs from 32-1156kW. Featuring stainless steel heat exchangers and modular configurations, these high-efficiency gas boilers deliver reliable commercial heating for schools, hotels, care homes, and apartment buildings. Available in the Genesis 32 (32kW system and combi), Genesis WM wall hung (41-149kW), Genesis FS floor standing (124-300kW), and Genesis FS Plus (318-1156kW), our condensing boilers provide powerful, efficient heating solutions for commercial properties across the UK.

Electric Boilers

Modutherm's Genesis Eco electric boiler range delivers 99.9% efficiency with outputs from 36-504kW across 13 floor standing models. Featuring modular configurations and zero-carbon operation, these commercial electric boilers provide reliable heating for schools, offices, apartment buildings, and commercial properties. Ideal for new builds, hybrid heating systems, and applications without gas supply, Genesis Eco electric boilers offer a sustainable, low-maintenance heating solution for commercial heating projects across the UK.

Hot Water Production

Modutherm offers comprehensive commercial hot water solutions including stainless steel and Polywarm® calorifiers (200-3000L), heat pump calorifiers (200-1000L), and plate heat exchangers for instantaneous hot water production. Our Juniper range features tank-in-tank calorifiers, heat pump thermal exchange cylinders, and the Juniper HP Plus exhaust air heat pump water heater (200-300L). Combined with the CoilMaster gas-fired water heater and Juniper PRS plate heat exchangers, Modutherm delivers efficient large-scale domestic hot water storage and production for hotels, schools, apartment buildings, care facilities, and commercial properties across the UK.

Commercial Hot Water Calorifiers

Heat Pump Calorifiers

Exhaust Air Heat Pump Water Heater

Instantaneous Hot Water Production

Buffer Vessels / Thermal Stores

Modutherm's comprehensive range of buffer vessels, thermal stores, and expansion vessels (200-20,000L) complement commercial heating systems including boilers, heat pumps, and heat networks. Our mild steel buffer vessels include Standard (200-5000L), Compact (2500-8000L), Heat Pump specific (500-5000L), Flanged Connection (2500-20,000L), and External (500-5000L) models, plus expansion vessels (24-500L). Designed for optimal thermal storage and system efficiency, Modutherm buffer vessels are ideal for commercial properties, schools, care facilities, apartment buildings, and heat pump installations across the UK.