Have you experienced issues with heat pump sizing or performance in cold weather?

Yes, my heat pump struggles to keep the house warm in cold weather (0C or below)

I thought the system was correctly sized, but it underperforms when it’s cold

I’m unsure if it’s correctly sized... it works most of the time, but not always in winter

No issues. The system keeps the house warm, even in cold weather

The installer did a heat loss calculation and matched the heat pump to it exactly in kW

My heat pump size does not match our heat loss calculation

I have no idea if my heat loss calculation matches up against the size of the heat pump

I’m not sure if a heat loss calculation was ever done