10 September 2020
Mitsubishi Electric has launched a new commercial heating system running on CO2 (R744) refrigerant, which it says delivers hot water at up to 90°C and can help businesses increase the efficiency of hot water production whilst reducing their carbon footprint.
The 40kW Ecodan QAHV high temperature air source heat pump is designed for commercial sanitary hot water applications in hotels, leisure centres, hospitals, care homes, restaurants, schools and universities.
Traditionally these are areas where gas boilers, combined heat and power systems (CHP) or electric water heating have dominated, but as the national grid has become ‘greener’ and decarbonised, the case for modern, electrically-powered air source heat pumps has become stronger and stronger.
“This new unit is the perfect choice for organisations looking to meet their carbon reduction plan, and offers a low carbon solution that utilises the natural and stable refrigerant CO2,” said James Chaplen, Senior Product Manager responsible for the QAHV. “These high performing units deliver an environmentally clean solution that enables compliance to strict local planning laws and helps to boost BREEAM points.''
Capable of flow temperatures from 55°C up to 90°C, the QAHV can produce large delta T’s when it maintains an inlet water temperature lower than 29°C. This also enables it to achieve a Coefficient of Performance (COP) of 3.88.
Seasonal efficiencies of the QAHV when producing sanitary hot water at 65°C have also been calculated to be 3 which, when compared to a typical gas boiler, can equate to overall carbon savings of up to 78%. These high levels of efficiency also provide significant savings in running costs and carbon emissions against direct electric heating systems.
“Commercial heat pumps have been proven to be incredibly efficient for low temperature heating but they have struggled to show the same levels of carbon savings when producing sanitary hot water,” explains Chaplen. “The Ecodan QAHV has been designed specifically to address this and, with the use of CO2, it also helps future-proof businesses in line with the next phases of the F-Gas Regulations.”
The QAHV is designed to deliver high efficiency at high flow temperatures and uses a unique and patented twisted and spiral gas cooler to enhance energy efficiency. Three connected refrigerant pipes are wound around a twisted water pipe which maximizes heat transfer. The continuous spiral grooves in the twisted pipe accelerates the turbulence effect of water and also helps to reduce pressure loss within the heat exchanger which contributes to enhance efficiency.
Equipped with Mitsubishi Electric’s latest inverter scroll compressor technology, the QAHV can significantly increase the annual efficiency of a building. R744 has a Global GWP of 1, yet the unit can still provide full heating capacity down to -3°C outdoor temperature and operate efficiently and effectively right down to -25°C.
“We’re launching the QAHV at a time when interest in high temperature heat pumps is growing due to the decarbonisation of the grid,” added Chaplen. “We’ve designed the QAHV to outperform other type of high temperature air source heat pump currently available on the market.”
The QAHV is said to deliver significant improvements over current high temperature heat pumps including low noise levels of only 56 dB(A). Up to three BREEAM points can be achieved with the use of the QAHV, with 2 points through the use of CO2 as the refrigerant and another one point from the fact that the circuit is hermetically sealed.
In addition to all of these improvements, because it is designed as an indirect system, the heat exchanger is protected in hard water areas and there is no requirement for the Water Regulations Advisory Scheme (WRAS) approval. At the same time, the system still meets all Health & Safety Executive guidance for Legionella.
“We are expecting a lot of interest from designers of places such as hotels, hospitals and student accommodation but the system will work equally well in manufacturing processes or anywhere needing high volume and high temperature sanitary hot water,” adds Chaplen. “We can install the QAHV in a modular array of up to 16 units allowing for a total capacity of 640kW per system.”
Overall, the new unit is aimed at anyone with strong carbon reduction targets who needs sustainable, energy efficient hot water production.
Further details can be found here.
Mitsubishi Electric is hosting a webinar next week on the new QAHV and the role commercial heat pumps can play in the built environment. The event takes place on September 17 at 2pm and registrations are open to all here.