Why Does My Heat Pump Freeze Up in Winter?
Frost on a heat pump is usually normal and self-clearing. How defrost works, what separates ordinary frost from a fault, and why ground loops freeze too.
Updated 8 October 20267 min read
Topic
Geothermal & Heat Pumps
Heat pumps and geothermal systems move heat rather than burn fuel to make it. Learn the refrigeration cycle and the COP, and the rest of the field follows.
A heat pump is a refrigerator run for its warm side: a refrigerant evaporates where it is cold, is compressed, and gives up its heat where it is warm. Because it moves heat instead of generating it, one unit of electricity can deliver several units of heat — and how many depends mostly on the temperature difference the machine has to work across.
That single idea answers the questions in this section. It explains why the shallow ground, which holds a nearly steady temperature all year, makes such a good heat source; why a ground-source system keeps its performance through a cold snap while an air-source unit loses capacity just as the building needs it most; and how closed-loop and open-loop ground systems trade thermal performance against water handling and upkeep.
There is a troubleshooting side as well: why outdoor coils frost over in winter, how a defrost cycle clears them, and which symptoms point to a fault rather than normal operation. All of it is explained from the physics outward, in metric and imperial units, with no product recommendations or prices.
How Do Geothermal Heat Pumps Work?
A ground-source heat pump moves heat between a building and the soil with a refrigerant cycle. Why shallow ground is a good source, and what sets the COP.
Updated 8 October 20267 min read
Ground-Source vs Air-Source Heat Pumps in Extreme Cold
In deep cold an air-source heat pump loses capacity as demand peaks, while a ground loop barely notices. Why that happens, and what modern machines changed.
Updated 8 October 20267 min read
Closed-Loop vs Open-Loop Geothermal Systems
One circulates its own fluid forever; the other pumps groundwater through and returns it. The heat-transfer gain, the water chemistry, and how to choose.
Updated 8 October 20267 min read