This morning when I got my bike out of the yard to take Juniorette to school, I heard a loud clattering noise from the box-like outdoor part of our air source heat pump. At first I thought the ball bearing on the rotor had crapped out. But the guy who installed it explained over the phone that the problem was most likely not as severe as that.
A heat pump like ours dribbles condensation water through a spigot on the under side. It’s been an unusually cold winter, and so the water has collected as ice on the ground beneath the box, building up layer by layer until it made contact with the casing and blocked the spigot. Then the water started to collect and freeze inside the machine. The clattering noise is caused by the rotor blades hitting an ice ridge, which is plainly visible if you shine a light into the thing.
Coming home today, I shoveled away the snow around the heat pump box and poured three buckets of hot water onto the ice floe under it. Then I used a spade, an electric drill and a small axe to remove the ice. Dunno how to get the ice out of the box before the temperature rises above freezing.
Live & learn. Next year I won’t let this happen.
Update 22 Fabruary: Turned out all I needed to get the ice out of the box was a screwdriver and an axe.