Why Heat Pumps Make Sense

By Bud Hammer

The first thing to understand about HVAC technology is that there isn’t anything called cold, instead we focus on transferring heat from one place to another. A typical residential style air conditioning system uses the physics of refrigerant to transfer heat from inside to outside during warm weather and the medium doing the work is refrigerant that gets pumped by a compressor. The air blowing inside may feel cold because it’s a lower temperature then our body, however the process we follow is called heat transfer.

With that basic understanding of how the process works, we can now talk about heat pumps. A heat pump is simply an air conditioning system that works in reverse when the temperature drops outside and the building needs heat. Again, the refrigerant is used to move the heat via the compressor (or pump). There are 2 common types of heat pumps: air source and water source. Air source means there’s equipment outside that uses air to add or remove heat from the refrigerant via a fan that spins. Water source means water (or similar fluid) travels through a heat exchanger that will add or remove heat (can be a cooling tower, boiler, or the ground as in geo-thermal). Even in cold climates such as the northeast, while it may seem frigid during the winter months, the refrigerant is cold enough and through physics, able to absorb enough heat to make the inside comfortable. It’s all about transferring heat from one space to another.

In the mid-2000’s, our industry started using a refrigerant (R-410a), that made heat pumps in cold climates a viable solution. Geo-thermal heat pumps that use the earth as the heat exchanger are very efficient to operate. Air source heat pumps are efficient as well. Currently utilities in NY state are heavily incentivizing building owners to install heat pump technology and it’s important to consider when adding or replacing a system.