When you’re faced with an HVAC system replacement, consider a heat pump, one of the best options for our climate. Heat pumps do double-duty year-round because they both heat and cool. They’re one of the most energy efficient options for a climate like ours, since winters are so mild.
How Heat Pumps Work
Heat pumps function just like a refrigerator, taking heat energy out of one space and moving it to another. In the winter, the pump extracts heat from the air to warm the refrigerant, which it sends into the evaporator coil in the air handler. The air flowing over the coil is heated and distributed throughout your home through the ducts.
In the summer, the process reverses and the pump pulls the warm air indoors over the coil and the cold refrigerant absorbs the heat. It flows out of your home and the outdoor condenser pulls air over it, removing the heat. The compressor cools the refrigerant before sending it back into your home.
Heat Pump Efficiency
The minimum efficiency standards that apply to a heat pump is its SEER (seasonal energy efficiency ratio) rating and its HSPF (heating season performance factor). The minimum SEER available is 13 and the HSPF is 7.7. You can find heat pumps with SEER ratings into the 20s and HSPF ratings into the 10s. In our climate, a pump that has a higher SEER lowers your energy bills since the cooling season is so prolonged and intense in this climate.
Some of the features that improve the energy efficiency of a pump include:
- Two-speed compressors. These systems sense how much heating or cooling your home needs and operate on a lower speed when you need less. When the system is equipped with a variable-speed motor in the air handler, it’ll improve your home’s air quality and dehumidification in the summer. When it runs at a lower speed, it stays on longer and you’ll have better air filtration and humidity removal.
- Thermal expansion valve (TXV). This is another feature that improves efficiency because it adjusts the amount of refrigerant to send to your home based on conditioning needs.
- Electronically commutated motors (ECMs). These motors are brushless and run more quietly than the more commonly used motor called a permanent split capacitor (PSC) motor. They’re more durable and use far less electricity than the PSC.
- Scroll compressors. These compressors run much more efficiently than a piston compressor and will increase heat output by 10 to 15 degrees F. This compressor runs somewhat more quietly than the piston compressor, making the outdoor condenser quieter.
- Desuperheater. This option in a heat pump can heat your water in the summer or a swimming pool or hot tub. It transfers the waste heat from your home and heats water much more efficiently than your water heater. Since your water heater is second in line for increasing utility bills, selecting this option will cut energy bills.
- Thermostat. Pumps have a supplemental electric coil that turns on when your home needs more heat than the pump can deliver. If you turn your system down at night, it may turn on the electric coil, which uses three times the electricity than the pump uses. However, an intelligent recovery thermostat overrides the coil and runs the pump more often throughout the night.
It’s crucial that your HVAC contractor conduct a load calculation for your home before installing it. Contractors use software called Manual J to arrive at the system’s sizing, taking into account the size of the home, its energy efficiency, floorplan design and your lifestyle.
Systems that are too large will run in shorter cycles more frequently. This increases energy bills, wears the parts and reduces humidity removal in the summer. The evaporator coil won’t get as cold, and it’s this part that condenses the water vapor. Frequent starts and stops don’t allow the coil to cool enough. A system that’s too small may not be capable of cooling your home during excessively hot weather.
The load calculation will also show you how you can improve your home’s energy efficiency. Improving attic insulation and sealing air leaks are affordable projects that could result in a smaller heat pump that will cost less to buy and run.
To learn more about why a heat pump is a good choice for your home, contact the pros at Gulf Coast Air Systems, serving homeowners in the Brandon, Riverview, Lithia, Valrico, Sun City Center and Plant City areas for more than 30 years.