HVAC Terms & Technology
When shopping for a new heating and cooling system, the unfamiliar terms and technology can be a bit overwhelming. The below definitions will help you understand the most common terms you’ll come across during your buying decision.
Heating Performance & Efficiency
AFUE (Heating Efficiency)
Annual fuel utilization efficiency measures heating fuel usage. The higher the AFUE rating, the more efficient the heating unit.
HSPF (Heating Efficiency)
Heating seasonal performance factor measures the heating efficiency of a heat pump. The higher the number, the more efficient the unit.
BTU (Heating Efficiency)
British thermal unit represents the amount of energy needed to raise the temperature of one pound of water by one degree Fahrenheit.
Two-Stage / Single-Stage Gas Valve
Much like a two-stage compressor, a two-stage gas valve also performs at two levels or capacities of operation. The heating system will either perform at a high-level of operation when there is a significant call for heat or in a more energy efficient, low-level of operation when maintaining indoor temperatures. A single-stage gas valve performs at a single level of operation and is either off or on.
Modulating Gas Valve
Unlike single and two-stage gas valves, a modulating gas valve adapts its output to the precise needs of the home with tiny 1% adjustments between 40-100% capacity. Modulating furnaces operate with more finesse to reduce temperature swings, provide consistent indoor temperature, quiet operation and superior efficiency.
Variable-Speed Blower Motor
A variable-speed blower motor automatically adjusts the flow of warm or cool air circulating throughout the home for maximum comfort control. Variable-speed systems are great for boosting HVAC system efficiency and improving summer dehumidification.
Air Conditioning Performance & Efficiency
SEER (Cooling Efficiency)
Seasonal energy efficiency ratio measures cooling efficiency in air conditioners and heat pumps. The higher the SEER, the more efficient the unit.
Ton (Cooling Capacity)
A ton is the cooling capacity of an air conditioner. One ton is equal to the amount of heat required to melt one ton of ice in a 24-hour period.
Two-Stage / Single-Stage Compressor
Two-stage compression performs at two levels or capacities of operation; low and high. The system is designed to perform at the low level most frequently to allow for quieter operation, greatest efficiency and best dehumidification. During extremely hot weather conditions, the system will perform at high capacity operation in order to keep up with cooling demands of the home. A single-stage compressor performs at a single level of operation and is either off or on.
Variable-speed compressors operate at five levels or capacities of operation. The ability for a compressor to step up or down in 5 stages means that the system is capable of delivering the most superior performance in terms of quiet, humidity control, consistent temperatures and unprecedented energy efficiency.