> But a well designed system to match worst case load should rarely see this. Well actually it'll see it quite often. Every time a heat pump goes into defrost

> But a well designed system to match worst case load should rarely see this. Well actually it'll see it quite often. Every time a heat pump goes into defrost mode it'll use resistive heating inside to hold over while it's working like a traditional air conditioner to thaw out the outdoor coils.