As an air to water monobloc heat pump, it operates effectively applying eco-friendly R290 refrigerant, furnishing sustainable heating with an impressive A+++ energy efficiency rating. Most of the maintenance demands for air source heat pumps reflect that of conventional air con and furnace installations, for instance standard air filter replacements https://purethermal.co.uk/media-news/q4-launch-lithium-large-capacity-r290-ashp-from-pure-thermal-and-enerblue/