When it comes to lower-energy home heating, it’s accurate in all senses to say that heat pumps are the new hotness. But unless you happen to work with them professionally, it’s fair to say their inner workings are beyond most of us. Help is at hand though courtesy of [petey53], who made his own ground source heat pump for his Toronto house using a pair of window-mounted air conditioning units.
An aircon unit is a heat pump that’s designed to scavenge heat from the air indoors and dump it into the warmer air outside. Thus it’s ideally suited to the task of doing the opposite, but the clever part lies in how he uses it as a ground source pump rather than an air source.
He carefully bent the tubing of the aircon to allow hot and cold radiators to sit in water baths, with the hot side feeding an underfloor heating loop and the cold side is a long length of pipe buried in the garden. Meanwhile, a Raspberry Pi paired with a repurposed Droid Alpha robot controller runs the pumps.
It’s exciting to see a relatively simple route into having a heat pump, and we’d hope to see more coming our way over time. We’ve seen geothermal PC cooling. Far more common, so far, have been heat pump controllers.