Heat pumps are an increasingly popular replacement for central air systems, but it can be difficult to determine which one is right for your home. It can even be difficult to understand the differences between the two. We will give you a brief overview of each system and how they work, and then we will discuss whether a heat pump vs central air is best for your home.
Central Air
A central air conditioner works by transferring the heat inside your home to the air outside your home. Fans pull air into your house over an evaporation coil; this coil is full of refrigerant that enters the coil in a pressurized, liquid state. As it is pumped through the coil, the pressure is released, and it reverts to its natural state as a gas. As it evaporates into a gas, it absorbs heat. This is because the process of evaporation naturally uses heat. The refrigerant, now heated into a gas, is then pumped into the condenser coil outside your home, where another fan pulls outside air over the coil. As the refrigerant is pumped into the condenser coil, it is pressurized again to condense it into a liquid, a process that naturally releases heat. The outside air blows over the coil, which then carries the heat away.
Heat Pump
A heat pump uses the exact same mechanism as central air. The only difference between the two is that a heat pump has a reverse valve that allows it to flip the process. While a central air unit can only move heat from inside the house to the outside, a heat pump can also move heat from outside the house to the inside. This process will even work on cold days. Even on a cold day, there is heat in the air.
Heat is simply a way of measuring energy. Heat is the vibration of atoms in a substance that is caused by the amount of energy stored in it. So, cold air still has heat because it still has energy. It just has less energy than warmer air, or your body, so it feels cold. A heat pump in cooling mode is no different from an air conditioner. A heat pump in heat mode evaporates refrigerant in the outside coil, condensing it inside the coil. In this way, the heat pump forcibly removes heat, even from cold air, and transfers into your home. Again, this works because evaporating the cooling air pulls heat from the air, even if the evaporation is caused by depressurization rather than direct heating. Since any evaporation uses heat, the cause of the evaporation does not matter. As long as the liquid is evaporating, it is absorbing heat. This is what allows the heat pump to pull heat from cold air.
Which is better, Heat Pump Vs Central Air?
This all depends on where you live.
Both systems will cool your home effectively, using the same process. A central air unit, however, cannot heat your home. If you live in a climate in which heating your home is unnecessary, then you have no need for a heat pump.
It is also possible that you live in a region where the weather gets too cold for a heat pump to work. Although heat pumps can work in cold weather, they do have their limits. If the weather is cold enough, you will still need a furnace. Generally, heat pumps remain effective down into the mid-30s. Anything colder then that and a heat pump simply cannot generate enough heat.
That does not mean that they are useless in a colder climate, though. Heat pumps can make your furnace more efficient by warming the air before it gets to the furnace. This way, your furnace does not have to work so hard to provide a comfortable level of heat.
A heat pump is much more energy-efficient than a furnace, too. So, even with both running there is a good chance that you will save money by installing a heat pump.
Clearly, a heat pump is better for cooler climates and more useful in the winter. Heat pumps also require less maintenance than furnaces, because they do not use combustion to generate heat.
Heat pumps can be more expensive than central air, though, because they cost more to manufacture. Designing a system to reverse the flow of refrigerant and to be able to handle both pressurized and evaporated refrigerant in both coils is costly. So, the up-front costs of a heat pump are higher. A heat pump will also wear out faster and require more maintenance in general compared to a central air unit since a central air unit will only be used during the warmer months. It is not in use for much of the year. So, while it will generally have many of the same maintenance requirements as a heat pump, it should need maintenance less often.
If you live in a warm climate, or if you already have a furnace installed, it may not be worth the extra cost to purchase a heat pump instead of central air. For many of you, though, a heat pump, despite the increased up-front cost, can save you a lot of money on your energy bills in winter. If you live in a cooler climate, but one that is still quite mild, a heat pump is ideal because you will not need a furnace at all. This applies to much of the United States. If the winters where you live are cold but not harsh, it is probably worth the extra cost to buy a heat pump instead of an air conditioner.
However, if you find yourself only rarely turning on the heater in winter, then there is little reason to purchase a heat pump, as an air conditioner will meet your needs.
If you have any more questions, or if you would like to schedule a consultation with heating and cooling experts, contact Presidential Heating and Air. The professional staff will be happy to assist you with anything you need.