I think when I did the numbers for our heat pump, a catastrophic leak that would release all its refrigerant would result in a GHG contribution equivalent to a year of emissions from our (previous) natural gas heating. Can't find the figures now so do check before quoting me on it ;)
Alternatively, Mitsubishi has been selling a first-generation product that uses CO2 as the refrigerant (the QUHZ model). It posts a COP of 3 for producing domestic hot water (that's pretty good) - I'm not sure why they don't post the COP for room heating, maybe it's not great. But I'm curious what the second-generation product will do!
Alternatively, Mitsubishi has been selling a first-generation product that uses CO2 as the refrigerant (the QUHZ model). It posts a COP of 3 for producing domestic hot water (that's pretty good) - I'm not sure why they don't post the COP for room heating, maybe it's not great. But I'm curious what the second-generation product will do!