It may be time to replace your heating, ventilation, and air conditioning (HVAC) equipment if it is more than 10 years old, not keeping your home comfortable, or needs frequent repairs. Replacing existing equipment with a high efficiency system can save up to 20% on your heating and cooling costs. In addition, properly sizing new equipment may allow you home to use a smaller unit, which will save money on the cost of the unit and energy bills for years to come. A professional Quality Contractor Network (QCN) member can evaluate your equipment and offer solutions for your home.
What size HVAC system do I need?
HVAC equipment needs to be properly sized to perform at its best. An oversized heat pump or air conditioner wastes energy and costs your money. When replacing heating and cooling equipment, a trained QCN member will need to calculate your home’s heating and cooling needs to determine the proper equipment size for your home.
How is the energy efficiency of a heat pump rated?
Heat pumps have to efficiency ratings: Seasonal Energy Efficiency Ratio (SEER) for the cooling mode and Heating Seasonal Performance Factor (HSPF) for the heating mode. Higher SEER and HSPF numbers equates to higher levels of energy efficiency. Higher efficiency heat pumps have a SEER of 14.0 or greater for packaged units and 14.5 or greater for split units, and a HSPF of 8.0 or greater for packaged units and 8.2 or greater for split units. Be aware that equipment efficiency degrades over time, so a 15- year-old unit rated SEER 12 easily could be operating like a SEER 10 unit.
How is the energy efficiency of an air conditioner rated?
Air conditioner efficiency is rated by SEER. Typical air conditioners manufactured today have a SEER ranging from 14 to 18, while a 12-year-old air conditioner might have a SEER of 10. Higher efficiency air conditioners have a SEER of 14.0 or greater for packaged units and 14.5 or greater for split units. In general, a SEER 16 air conditioner will use 33% less energy compared to an air conditioner rated SEER 12.
What factors affect the performance of my new HVAC system?
Heating and cooling accounts for approximately 45% of the energy used in a typical home. In order to optimize the performance of a new heat pump or air conditioner, it is important to first improve the overall energy efficiency of your home by insulating ceilings and walls to recommended R-values, sealing and insulating any ducts located in attics, crawlspaces, and unheated basements, and air sealing the home. These improvements may allow your home to use a smaller unit, saving you money on the cost of your new system and your energy bills. In addition, an improper installation can reduce system efficiency by up to 30%, so its important to ensure that new equipment is properly installed.
TVA Installation Requirements for HVAC Replacement
- Moisture issues shall be resolved before work begins.
- Balance point shall not exceed 35℉ (heat pump only).
- Contractor shall size, select, and install equipment according to Manual J and TVA requirements.
- Total cooling capacity shall be between 95% and 125% of total cooling load (sensible and latent) or the next largest nominal piece of equipment.
- Equipment operating capacity shall be within 10% of equipment rated capacity.
- All equipment shall be AHRI certified and meet TVA Minimum Efficiency Requirements for Heating and Cooling.
- Outdoor units meet TVA clearances for intake (18″) and discharge (4 feet), and shall not be located 4 feet of kitchen or laundry exhausts.
- Airflow shall be within the range recommended by manufacturer (normally 350 cubic feet per minute [cfm] to 450 cfm per ton).
- Supply registers shall have an average face velocity between 400 feet per minute (fpm) and 700 fpm, or per manufacturer’s recommendations.
- Where possible, the return shall be continuously wrapped in a minimum of 3/8″ insulation and vapor sealed.
- Condensate drain shall be at least ¾ “, trapped at unit, and made of copper or plastic. Condensate shall always drain to the exterior.
- The first 6 feet of condensate line shall be insulated.
- Float switch shall be installed on auxiliary drain pan or condensate drain.
- New and existing ducts shall be securely supported; support shall not constrict ducts or duct insulation.
- Ducts shall not contact the ground.
- Exterior ducts shall meet all applicable TVA Duct System Standards.
- A minimum of one return air grille is located on each level of the home.
- Quality Contractor Network (QCN) member shall visually inspect duct system for damage and provide participant with a quote for making repairs.
- QCN members shall advise participant to install a working carbon monoxide (CO) monitor if the home has any gas appliances or an attached garage.
* This sheet is not a substitute for the TVA Standards.
** TVA Minimum Efficiency Requirements for Heating and Cooling are not applicable.