Is it time to replace your furnace? if so, a heat pump may be the best option to keep your home warm and save you money.
Almost all of us have that moment in our lives when we know it’s time to say goodbye. Hot in the summer, cold in the winter, high energy charges, unreliable operation. The romance with our furnace or a/c system is over.
You start looking for a new system and soon run across an intriguing alternative: a heat pump system. But what is that, exactly and can a furnace really replace it? The answer is yes—and it can be a good option for homeowners who:
- Live in a moderate climate. You’re in luck! The Seattle area has an ideal climate to maximize the benefits of a heat pump. We don’t typically experience long periods of extreme temperatures, either high or low, and that’s the sweet spot for a heat pump.
- Have a well-insulated home. Insulation helps to maintain a steady temperature in your home year-round. And, honestly, it’s something you should invest in, whether you have a heat pump or any other type of system.
- Like to save money. While it costs more to purchase and install, replacing your furnace and air conditioner with a heat pump can quickly pay for itself in lower energy and fuel consumption. In mild climates, heat pumps can achieve 300% to 400% efficiency. That means it delivers three to four times the energy it consumes!
- Have a heart for protecting our environment. Heat pumps run entirely on electricity and therefore create a smaller carbon footprint than systems that run on fossil fuels. With a heat pump, you’re helping to heal and preserve our climate for future generations.
- Enjoy a little peace and quiet in their homes. In general, heat pumps run more quietly than conventional furnaces and air conditioning systems.
What is a Heat Pump?
Although it’s called a heat pump, one single unit can actually replace your furnace and your air conditioning unit. That’s because a heat pump doesn’t create heat or cold. Instead, it transfers thermal energy—molecules in motion. When fast-moving molecules collide with slower ones, we feel it as heat. On the other hand, we feel cold as a result of slower-moving molecules. But it’s all the same energy..
A heat pump takes that energy and processes it through a refrigerant and other components. In the summer, the heat pump processes and transfers the fast-moving molecules in your hot house to the outside to cool it. In the winter, it processes outdoor thermal energy and brings it inside to warm your house.
Keep reading to learn more about how this works.
There are several types of heat pumps, but the two most common for single-family homes in the Pacific Northwest are air-source heat pumps and ground-source (geothermal) heat pumps. Both types use the same principle of heat transference, but there are a few differences.
Heat and Cold From Thin Air
Air-source heat pumps, like the name implies, use outside air to perform their heating and cooling magic. In the winter, the unit extracts thermal energy from outdoor air. Believe it or not, modern heat pump technology enables the unit to produce heat for your home from outdoor air as cold as -15° Fahrenheit! The system’s refrigerant absorbs the thermal energy and evaporates it into a gas, then a compressor increases the temperature of the gas as it flows into your home. And, voila! Heat from what was recently cold air.
In the summer, the heat pump works like a regular AC, absorbing excess heat inside your home and sending it outside, where it’s released into the air, leaving slow-moving molecules—cooler air—inside your home. Even better, this process also dehumidifies indoor air—a welcome bonus in Seattle’s humid climate.
Air source heat pumps usually work best in mild climates, like our Pacific Northwest climate, and they typically last for about 15 years. Because they’re installed above ground, they are easier to install and, therefore, typically less expensive than ground-source heat pumps.
if it is cold outside, there is no heat in the outside air
Harnessing the Power of the Earth
Ground-source heat pumps rely on the steady temperature of the earth—warmer than surface air in winter and cooler in summer—to turn warm air in your house to cool air and vice-versa. In Seattle, the vertical loop style of ground-source heat pumps may be buried six to 10 feet below the ground, depending on factors such as the composition of the soil on your property and the depth of the local water table.
Not surprisingly, a ground-source heat pump works similarly to air-source heat pumps. In the winter, a fluid (usually water and antifreeze) absorbs heat from the earth as it circulates through looping underground pipes. That fluid then goes into the indoor unit, where it’s compressed and releases the heat to keep you warm and cozy.
In the summer, the ground works as a “heat sink.” Your heat pump system removes heat from your home using the fluid in the system, then transfers that heat outdoors and deposits it in the ground.
Because it uses the earth to transfer heat energy, an in-ground heat pump works in any climate. Systems require excavation or drilling for their installation, though, so initial costs may be higher than the cost of air-source heat pumps. However, systems are very efficient and cost less to operate in the long run, and the in-ground component of the system can last 50 years or more.
The Key to a Long-Lasting Heat Pump System
To prolong the life of your heat pump, keep it running at maximum efficiency and protect your warranty, it’s important to perform routine and seasonal maintenance on your system. There are a few things you can take care of yourself, like changing or cleaning air filters, making sure vents and registers in your house aren’t covered by rugs, furniture or other obstructions, and keeping the outdoor unit free from debris like pine needles and leaves.
However, it’s wise to rely on home HVAC experts to perform some of the most important maintenance tasks on your system. That includes things like maintaining the proper refrigerant level, checking for leaks in the system, cleaning and lubricating certain parts, and checking for wear and damage in other parts. Learn more about heat pump system maintenance.
