Cold snap at 27°F and my air-source heat pump (backed by a 7 kW PV array) did such a dramatic defrost that a client on a video call asked if I’d installed a smoke machine; I swear it’s just clean heat doing theater… Anyone else collecting heat-pump misunderstandings while trying to save the planet one kWh at a time?
Had the same thing — neighbor once swore my unit went “full fog machine.” Quick win: hose off the outdoor coil and make sure the defrost sensor is seated/clean so it terminates fast; I also tell clients “it’s steam, not smoke” — what model are you running?
At 27°F, that ‘fog machine’ is normal — enable demand-defrost if your board supports it.
If it’s doing the full “steam show,” make sure the outdoor pad is slightly pitched and the drain path is clear so defrost runoff doesn’t create an ice rink. Co-sign @matthew9418 on demand-defrost — small caveat: if the coil sensor’s reading drifts, it can overstay the cycle; seeing any freeze-up around the base?
Your “clean heat doing theater” line is perfect. Is the outdoor unit in a windy alcove or aimed at a wall within a couple feet? A small wind baffle or reorienting the discharge can cut the plume and shorten defrost, and a pan heater kit is cheap insurance if ice starts piling up.