Optimisation of Air Source Heat Pumps in Residential Retrofits

• Main Authors: Seamus Hoyne, Padraic O'Reilly, Michael O'Shea
• Format: Article
• Language: English
• Published: Technological University Dublin 2020-11-01
• Series: Journal of Sustainable Design and Applied Research in Innovative Engineering of the Built Environment
• Subjects: Air source heat pump; retrofit; compressor cycle; defrost; commissioning; handover.
• Online Access: https://arrow.tudublin.ie/sdar/vol8/iss1/3

Correctly applied air source heat pumps (ASHPs) are a proven technology that can reliably and effectively replace fossil fuel heating systems and achieve targeted heating-related CO2 reductions. However, poor-quality system design, installation or commissioning can lead to higher than expected running costs and poorly-performing heating systems, thus resulting in lower than expected CO2 savings. The retrofit ASHP systems studied in this research in residential retrofits in Ireland had significant engineering input at design stage, and comprehensive oversight during the installation and commissioning stages by the engineering team. Following analysis, most of the systems performed in line with, or exceeded, predictions but further opportunities for optimisation were identified. The research highlights the need for increased focus and resources to be applied by commissioning engineers to ensure that all ASHP installations are successful, a point that is especially critical in the context of the Irish Climate Action Plan targets of 500,000 retrofitted homes and the installation of 400,000 retrofit heat pumps by 2030 (Government of Ireland, 2019). This paper presents recommendations on how the ASHP installation process can deliver systems that operate to their full potential in terms of energy efficiency and CO2 reductions.