Midland Road

Green Flare has designed and installed a renewable heating system for this seven-apartment property, comprising two air-source heat pumps and underfloor heating throughout.

LOCATION

Bristol

CONTROL SYSTEM

Roth

HEAT PUMP

Stiebel Eltron

ANNUAL CO₂ SAVINGS

4943kg

UNDERFLOOR HEATING

Roth

ESTIMATED SCOP

4.18

Overview

Green Flare was appointed to carry out the design and installation of a renewable heating system for this seven-apartment property near the centre of Bristol. To reduce the cost of installation and cost of ownership, the client decided to use a communal heat pump to provide heat and hot water.

Technology

After we reviewed the building plans in detail, we designed a bespoke renewable energy heating system to satisfy the needs of this new seven-apartment property. The set-up consists of two Stiebel Eltron WPL-A 07 air source heat pumps, chosen for their reliability, quiet performance, and high efficiency, even in sub-zero temperatures. These units provide both heating and hot water for the whole building with the ability to reach flow temperatures of 75°C, making them ideal for year-round comfort.

The heat pumps are fully integrated with an underfloor heating system, which we installed throughout all the apartments. We used the Roth Knob System for its flexibility and ease of installation, ensuring an even and efficient heat distribution across every room. This low-temperature system operates seamlessly with the heat pumps to minimise energy consumption while maintaining a consistently warm environment.

To allow residents full control over their comfort, we also installed the Roth Touchline SL control system, which enables individual room settings. The Touchline SL also allows the landlord to remotely monitor and control the heating so that when the apartments are unoccupied, the room temperatures can be lowered. This system has been upgraded with the Roth Touchline Wi-Fi module to allow the residents to control their system from a mobile app, giving users both flexibility and peace of mind.

Challenges

One of the key challenges on this project was that the building had not originally been designed to accommodate a communal heating system. This required careful coordination to identify suitable service voids and risers for routing pipework from the detached plantroom to each apartment.

The heat pumps are connected in a cascade to allow them to work together as a pair, providing heat to a 200L buffer tank and two 500L glass-lined domestic hot water cylinders, which supply hot water to the seven apartments. The 500L cylinders have been installed in parallel with a timed and temperature-controlled secondary return pump, giving instantaneous hot water to each apartment.

The separation of the plantroom also meant installing below-ground heating mains, making the installation more complex. In addition, external space was limited due to the city centre location. This required precise selection and positioning of the heat pumps, ensuring compatibility with the synthetic refrigerant available and mindful of proximity to neighbouring properties.

"We chose Matt and Tom at Green Flare to design and install our communal air source heat pumps on this project as they came up with a simple solution using quality equipment that fitted our budget. They were very flexible and talked us through the options without getting too technical. The system works well and is simple to use and control. Their installers did a great job with the installation and were always helpful. A very capable and professional contractor that we would not hesitate to recommend for future developments."

- Jack Tovey, BCE Electrical Contractor