While the ductless heat pump is still relatively uncommon in North America, it’s gaining popularity as an efficient, convenient way to heat and cool. This type of system is an especially good choice for the Sarasota and Bradenton area’s mild climate. Although many reliable manufacturers, such as Carrier, produce these systems, not all ductless heat pumps are created alike.
If you’re in the market for a ductless heat pump, one of the first things you’ll want to come to terms with is how these systems are rated for energy efficiency. When researching a system’s energy efficiency, there are four ratings to consider:
- Energy Star qualification
- CEE High-Efficiency Specification
HSPF (Heating Seasonal Performance Factor)
This is the rating you’ll need to look at to find out how a ductless heat pump will perform during the heating season. It’s a calculation of the amount of heat produced divided by the amount of electricity required to produce that heat. HSPF is expressed as a single number, such as 7 or 8.5. The higher the number, the more efficient the heat pump. While an HSPF of 6 or 7 is acceptable, if you want a high-efficiency system, look for one with an HSPF of 8 or higher.
HSPF is averaged out over the entire season, so it accounts for unusually warm and cold days throughout the winter as well as early spring and late fall.
What it doesn’t take into account is backup heating. Backup or supplemental heating, found in conventional ducted heat pump systems, consists of an electrical heating element that turns on when temperatures fall much below freezing. This type of heating burns through energy quickly. HSPF doesn’t accurately reflect the heating efficiency of a system that uses the backup heating frequently.
With a ductless heat pump, especially in the warm Sarasota and Bradenton area, this is less of a problem. Ductless systems can work efficiently without backup heating in temperatures down to -4 degrees and our area rarely sees temperatures this low.
SEER (Seasonal Energy Efficiency Ratio)
SEER is the rating that tells you how efficient your ductless heat pump will be during the cooling season. Air conditioners also carry this rating. The calculation method is similar to that of the HSPF calculation. The total amount of cooling provided is divided by the energy consumed to provide that cooling. SEER is expressed as a single number, with a higher SEER indicating a more efficient system.
As with HSPF, the numbers used in the calculations are averages taken over the entire cooling season. The difference is that an outdoor temperature of 82 degrees and an indoor temperature of 80 degrees are used as baselines. Cooling in those temperatures doesn’t take much power, so it’s easy for a system to reach a high efficiency.
What’s more, these baselines aren’t particularly realistic for southwestern Florida, where temperatures range into the 90s for much of the summer. That means SEER, while useful, doesn’t give a completely accurate picture of a ductless heat pump’s cooling efficiency.
Nonetheless, it’s still worth considering. For acceptable cooling efficiency, look for a system with a SEER of around 14 to 16. Ideally, though, aim to find one with a SEER of 20 or higher.
EER (energy efficiency ratio) is another rating to be aware of. Like SEER, EER is calculated by dividing the cooling energy output by the electrical energy input. The difference is that EER isn’t averaged out over the whole season. Because of this, EER is less useful than SEER.
The Energy Star Label
If you’ve gone shopping for household electronics in recent years, you no doubt have at least a passing acquaintance with this rating. Energy Star-qualified products are those that have met high efficiency specifications chosen by the U.S. Environmental Protection Agency (EPA).
Although a ductless heat pump works somewhat differently from a traditional system in that it doesn’t use ducts, ductless systems can still qualify for Energy Star status under the Energy Star specifications for central air conditioning (CAC) and heat pumps. To qualify, a split system heat pump must have an HSPF of 8.2 or higher, a SEER of 14.5 or higher, and an EER of 12 or higher. On average, qualified systems are around 9 percent more efficient than standard models.
These are the minimum requirements to qualify for the Energy Star label, but they’re by no means the highest efficiency ratings available. In fact, if you really want to save on your heating and cooling, look for a system that holds the Energy Star Most Efficient status. Some of these ductless heat pumps achieve an HSPF of 11 or higher and a SEER of 21 or higher.
The potential for rebates is another reason to choose an Energy Star-qualified system. Some utility companies offer rebates to homeowners who install high-efficiency heating and cooling.
CEE High-Efficiency Specification
CEE stands for Consortium for Energy Efficiency, a group of U.S. and Canadian energy efficiency program administrators who aim to encourage manufacturers, government agencies and service providers to get the most out of existing efficiency programs.
They also work to help bring more energy efficient products to the market and ensure greater access to these products. Ultimately, the group seeks to reduce energy use in order to lessen environmental impact, improve grid reliability and promote greater safety. The CEE won an EPA Climate Protection award for their efforts to preserve the environment by reducing energy consumption.
The CEE also provides rating guidelines, called the CEE High-Efficiency Specifications, for air conditioners and heat pumps. These are generally more stringent than Energy Star ratings.
The CEE Tier 1 rating for split system heat pumps is the same as the Energy Star requirements for these systems. For a split heat pump to reach CEE Tier 2, however, it will need an HSPF of 8.5 or higher, a SEER of 15 or higher, and an EER of 12.5 or higher.
Note that the CEE doesn’t qualify or endorse any specific manufacturer or products, so you won’t find a CEE-related label on any ductless heat pump. Instead, you’ll need to check the product’s yellow EnergyGuide label to find its HSPF, SEER and EER.
Other Factors to Consider
While energy efficiency is important, it’s not the only factor worth thinking about when you’re out shopping for your new ductless heat pump. A few other things you might want to look for include:
- Two-stage capabilities — Two-stage heat pumps have compressors and motors that can adjust their output to meet the amount of heating or cooling you need at the moment. Single-stage heat pumps run on high all the time, often reducing your comfort while running up your bills. A two-stage heat pump runs at a lower output when your heating or cooling demand is low, saving you energy and money while keeping your home at just the right temperature.
- A desuperheater — This is a secondary heat exchanger that uses excess heat to warm your hot water supply. It helps you save energy by giving you a way to use heat that would otherwise go wasted.
- Scroll compressors — These are more efficient, more durable and quieter than traditional reciprocating compressors.
- Indoor unit design — Ductless systems come with several types of indoor air handlers. High wall models mounted on the wall near the ceiling and cassette models mounted within the ceiling are two of the most common, but other designs are available. Before you buy, consider where you’ll want your indoor units.
To learn more about how a ductless heat pump could benefit your home or to get professional guidance choosing the right model, get in touch with us at Aqua Plumbing & Air. We serve homeowners throughout the Sarasota and Bradenton area.
Written by John Miller
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