This is a great question. Data from this website[0] suggests heat pumps leak at 6%/year vs. traditional condensing units which leak on average at 10%/year, so i

This is a great question. Data from this website[0] suggests heat pumps leak at 6%/year vs. traditional condensing units which leak on average at 10%/year, so it seems they are still an improvement over traditional ACs. One technician's experience[1] points to the steel accumulator rusting being the primary cause of heat pump leakage. There was a big 2014 study in the UK[2] on heat pump leakage, but no causes were identified, due to poor data collection. [0] https://support.accuvio.com/support/solutions/articles/4000040366-annual-leakage-rate-for-the-refrigeration-air-con-hvac- https://support.accuvio.com/support/solutions/articles/40000... [1] https://highperformancehvac.com/heat-pump-leaking-refrigerant-question/ https://highperformancehvac.com/heat-pump-leaking-refrigeran... [2] https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/303689/Eunomia_-_DECC_Refrigerants_in_Heat_Pumps_Final_Report.pdf https://assets.publishing.service.gov.uk/government/uploads/...