Mitsubishi pioneers heat pump retrofit solution
24th June 2025
UK: Mitsubishi Electric has joined forces with Sovereign Network Group (SNG) to deliver a pioneering heat pump retrofit programme using existing microbore/small bore domestic pipework.
Once thought incompatible with heat pump technology, the possibility of retaining microbore/small bore pipework of all types is seen as a game-changer for retrofit projects.
The use of Mitsubishi Electric’s Ecodan R290 high-temperature air-source heat pumps which work effectively and efficiently with legacy microbore/small bore systems will cut costs and reduce disruption.
The partnership with SNG, which manages more than 84,000 homes for 210,000 customers across London and southern England, could accelerate decarbonisation across SNG’s housing portfolio.
The scheme, based on Mitsubishi Electric and SNG’s extensive research and paper on microbore/small bore compatibility, removes one of the biggest barriers to large-scale heat pump retrofitting in older homes and could accelerate decarbonisation across SNG’s housing portfolio.
“This solution emerged from our desire to innovate and balance key priorities for both our customers and SNG,” said Jim Dyer, SNG’s built environment director. “It’s an ambitious holistic approach that places our customers’ wellbeing and operational cost-effectiveness at its core.”
The solution could enable heat pump systems installation can be as little as two days – around 40% quicker. As well as offering significant capital savings by retaining existing pipework and radiators, it also offers improved energy efficiency.
“The ability to retain microbore/small bore pipework of all types is a game-changer for retrofit projects,” commented James Chaplen, Mitsubishi Electric’s head of product marketing and communications.
“With our Ecodan heat pumps working effectively with existing systems, we’re removing a major financial and logistical hurdle. This opens the door for housing providers like SNG to scale-up their net zero efforts without compromising on resident comfort or driving up costs.”
