As a canny consumer and responsible homeowner, you want answers to questions about home-comfort systems before you invest your hard-earned dollars. Read through this introduction to ductless heat pumps, and you may discover that ductless systems have the right answers for your home-improvement project, and offer room to grow.
Start With Ratings
With so many advances in technology in the HVAC industry in recent years, it can be confusing trying to understand the differences in quality and performance between components, features and systems. So, a good place to start your home-comfort system research is at the bottom line.
The bottom line of a home-comfort system investment, with ongoing monthly energy bills, means the system’s lifetime costs – the sum of the purchase price, installation, operating costs, maintenance and repairs for life. That’s where energy-efficiency ratings come into focus. If you know one system offers 25 percent more cooling efficiency than another system by the SEER rating (Seasonal Energy Efficiency Ratio), you can do a quick estimate as to how much money you’re going to save each year for the next 15-20 years (ductless heat pumps last a long time).
Your HVAC professional also uses lifetime cost calculations to determine the point at which the higher purchase price of a more efficient ductless system pays for itself in energy savings. This is called the return on investment (ROI). From this point on, all energy savings are essentially dividends on your original high-efficiency, superior comfort investment.
Energy-Efficiency Stars and Their Ratings
Ductless heat pumps are among the most energy-efficient heating and cooling systems available. In fact, exceptional efficiency and versatile installation options are the driving forces behind the continued popularity and success of ductless technologies. This is apparent in the number of ductless systems that qualify for the Energy Star program.
You are probably familiar with Energy Star’s blue logo displayed on qualifying high-efficiency appliances. In short, Energy Star is a federal program designed to promote the manufacture and purchase of energy-saving appliances and products, from home-comfort systems and water heaters, to computers and TVs, to windows and insulation. If you want a higher-efficiency ductless system for your home, Energy Star qualifying systems should be criteria number one.
To qualify for the Energy Star program, ductless heat pumps must meet the following specifications:
- SEER (cooling efficiency) must be no less than 14.5, and HSPF (heating efficiency) must be no less than 8.2. SEER and HSPF are an estimated ratio of energy input (electricity) to cooling and heating output, respectively, during the course of the cooling and heating seasons.
- All Energy Star qualified systems must offer superior performance and reasonable time period for ROI compared to non-qualifying, less efficient systems in the same categories.
- For ductless heat pumps to qualify for Energy Star Most Efficient designation – the best of the best – a minimum 18 SEER and 9.6 HSPF are required.
Ductless Components: Room to Grow
Ductless heat pumps consist of generally the same components as their larger central heat pump cousins, but they are more versatile, compact and don’t require ductwork. Ductless systems may be a single-zone or multi-zone configuration, which is expandable if you decide to add more indoor air-handling units (AHUs) at a later time. Following are the three primary components that house all other ductless system parts:
- Outside cabinet – The outside cabinet houses the compressor, condenser, fan, drainage outlet and various electronics. It only requires a small concrete pad for mounting, or it may be mounted to the home’s exterior wall or flat roof. The compressor is the component that determines single or multi zones, with select models able to connect up to eight indoor AHUs.
- Conduit – A thin conduit houses the condensate tube, power supply and refrigerant lines. The conduit is installed inside inconspicuous areas (walls, attic, basement and/or crawl spaces), and requires a mere 3-4 inch hole in the home’s exterior wall and the interior wall on which the indoor AHU may be mounted (though other mounting options are available).
- Indoor AHU – The indoor AHU houses a fan, temperature sensors (room and coil temperatures), air filters and evaporator coil. The design of the compact AHU is key to ductless success. A conventional large central system has one evaporator coil that must be large enough to cool airflow for the entire home. A ductless AHU only needs to be large enough to cool one room or area. This point-of-use air distribution is efficient, practical and delivers premium zoned temperature control.
- Multi-zone – If you are only installing supplemental cooling for one room (zone), but you may expand later to other rooms, such as a sun room or retrofitted home office, it’s wise to go with a ductless multi-zone system.
Multiple AHU Mounting Options
Versatile installation options are one of the features that make ductless heat pumps very attractive heating and cooling solutions. The conduit may extend more than 200 feet, depending on the selected model. That leaves a lot of leeway for installing the outside cabinet and indoor AHUs in exactly the spaces you wish. It also allows you to heat and cool two or more zones that are far apart, including a detached pool house or workshop.
The indoor AHUs offer multiple mounting options to serve a host of interior design plans. The most popular AHU installation is universal high-wall or ceiling mounted. This installation type places the AHU cabinet flush to the surface of the wall or ceiling. You may also choose one of the following mounting options if it suits your project:
- Concealed – The AHU is concealed inside cavities in the wall, ceiling or floor. Only the diffuser is visible from the living spaces, giving the ductless system a smooth look of a conventional central system.
- Flex-duct – This is a concealed installation that uses a short duct run to provide air-supply diffusers and an air-return grille. This installation is excellent for larger zones.
- Recessed – If you are installing a drop ceiling in your room addition, office or other project, a recessed installation makes sense, with the AHU is installed above a ceiling panel.
Whichever mounting option you select, they deliver comfortable point-of-use airflow and are energy efficient.
Accommodating Home Applications
Ductless heat pumps have been in service for decades in commercial buildings and businesses. You may have spotted an AHU mounted on a wall or ceiling of an interior room of a large building, and wondered how the little box delivered nice and quiet cooling or heating without a window or ducts. Ductless heat pumps are designed to be installed just about anywhere. Following are examples that may be similar to your needs:
- Ductless heat pumps provide supplemental cooling and heating for those rooms in the home that are difficult to maintain comfort.
- Sun rooms, pool houses, guest houses, workshops and home offices may be tricky to install air conditioning that is practical, efficient and doesn’t require window space or a hole in the wall.
- Perhaps you do not want to extend ductwork to an attic and basement conversion.
- Perhaps your home does not have ductwork.
- New room additions to the home may be conditioned with a ductless system.
- Ductless systems are very competitive for installation expense in new home design since there is no ductwork to run. You also save valuable square footage.
- Ductless heat pumps are wise investments for rental properties, second homes, offices, churches and more.
Features to Look for
Ductless heat pumps are available with the latest technologies in comfort controls. You may use standard hand-held remotes, or go with a WiFi-enabled comfort control system that is accessible from your smartphone, work computer and tablet. Look for the following features to get the most out of your new system:
- Multi-phase filtration components remove common pollen, pet dander, contaminants and pathogens, and neutralize odors.
- Ductless heat pumps may provide energy-efficient water heating, and pool and spa heating with an add-on feature called a desuperheater.
- Look for ductless models with a digital inverter compressor. Inverter-driven technology offers whisper-quiet operation, and delivers superior cooling and heating efficiency.
Maintenance and Care
All home comfort systems need maintenance and care. Some tasks require professional expertise and certification, and some steps should be performed by the homeowner. With smaller components, ductless heat pumps are simple to maintain.
- Ductless system filters are usually washable and reusable. Check the filters monthly during peak usage, and rinse under cold water as needed. Let the filter completely air dry before reinserting.
- Check the outside cabinet on occasion to make sure there are no obstructions to airflow, such as leaves, wind-blown debris, garbage bins or grass clippings.
- About once a month, check to confirm drainage is flowing (or dripping) at the outside cabinet. Part of professional maintenance is treating the evaporator coil and condensate line for mold, mildew, algae, and other possible obstructions to heat exchange (evaporator) and free drainage.
That’s it. All other system checks, like conventional central systems, require an annual checkup by your HVAC professional.
For more details about ductless heat pumps, please contact us at Aqua Plumbing & Air. We service Sarasota, Bradenton and the surrounding area.
Written by John Miller
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