Heat pumps stand as powerful, efficient and increasingly popular alternatives to traditional central HVAC systems. Many still have questions about how heat pumps work and about both their similarities and their differences from those more typical options. If you’re thinking about installing a heat pump in your home in Goose Creek, SC, here’s some important information about heat pumps to get you started.
Some Background Information
Before diving into the weeds of how heat pumps work, some background information is in order. First, contrary to what their name might lead you to believe, it’s not true that heat pumps only have the ability to heat a room. They have both a heating and a cooling mode.
Secondly, heat pumps don’t actually generate heat in the way that a furnace might. Rather, they simply absorb heat energy from their surroundings and then move it to where it’s necessary. Ground-source or geothermal heat pumps do this by moving energy back and forth between the air in your home and an underground network of pipes, while air-source heat pumps transport heat from outdoor air to indoor air or vice versa.
Heat Pumps In Heating Mode
Heating mode is the mode you’ll most likely use in the fall. The key to seeing how heating mode works is to understand a counterintuitive fact: In this mode, your heat pump will use the outside air as a heat source, even if that air is very cold.
First, fans in the outdoor portion of your heat pump will suck in air that is presumably already rather cold but still contains at least some heat energy. The fans blow that air over the coils of the outdoor unit, which is full of liquid refrigerant. That refrigerant absorbs the heat energy in the air and passes through the reversing valve, which directs it to the compressor.
The compressor pressurizes the refrigerant, greatly increasing its temperature as a result. From there, the refrigerant moves into the system’s indoor unit and comes into contact with the cooler air there. Contact with this cooler air causes the refrigerant to cool and condense into liquid form.
The contact with indoor air and the condensation of the refrigerant are what generate the heating effect indoors. The now-warmed air moves through your ductwork and warms up your home. Finally, this liquid refrigerant moves into the system’s expansion valve, where it cools down even further and then travels back to the outdoor unit to begin the cycle again.
Heat Pumps In Cooling Mode
When a heat pump enters cooling mode, it reverses the process we’ve just described. Whereas in heating mode, the heat pump’s outdoor unit functions as an evaporator coil and its indoor unit functions as a condenser coil, cooling mode reverses these roles. This is possible because the reversing valve enables refrigerant to flow in the opposite direction from the one it takes while the pump is in heating mode.
In cooling mode, system fans blow warm indoor air over the coils of the indoor unit, and the liquid refrigerant in those indoor coils absorbs the air’s heat and turns into a gas. Fans then push the now-cooler air through your ventilation ducts, and the air cools your home.
As for the hot, gaseous refrigerant, it moves through the reversing valve and into the compressor, which pressurizes and heats it even more. Then, the refrigerant passes over the coils of the outdoor unit. Since the ambient air around those coils is cooler than the refrigerant, the refrigerant condenses and expels heat, allowing the cycle to repeat once more.
Because one mode is simply the reverse of the other mode, heat pumps can run on electricity and consume energy very efficiently. To enjoy the power of one of these incredible systems in your Goose Creek, SC, home this fall, call Berkeley Heating & Air Conditioning and request our heating installation services.
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