ERV, AFUE, SEER, BTU with so many acronyms in our industry it is easy for even professionals to be confused, here are some of the most common terms and definitions.
HVAC– Heating, Ventilation and Air-conditioning – This is the common term referring to the industry of indoor environmental comfort
AFUE is Annual Fuel Utilization Efficiency: The higher the AFUE the more efficient a furnace is. Think of it in terms of dollars. If you spend $100 of gas on heating an 80% furnace would waste $20 and a 95% furnace would waste $5 of that fuel. The waste occurs in gases vented outside. Choose a higher AFUE to save more energy.
BTU stands for British Thermal Unit, the unit of heat energy that’s necessary to raise the temperature of one pound of water one degree Fahrenheit, from 58.5 to 59.5. How does this apply to your home? A 10,000 Btu air conditioner can remove 10,000 Btus of heat per hour.
EER is the energy-efficiency ratio of a cooling system, it measures how efficiently the system will operate when the outdoor temperature is at a specific level (usually 95F). A higher EER means a higher efficiency.
What is the difference between EER and SEER? The SEER (seasonal energy-efficiency ratio) is a measure of air conditioning system’s efficiency over an entire cooling season, as opposed to a single outdoor temperature.
HSPF is a Heating System Performance Factor: This is the measure of a heat pump’s estimated seasonal heating output during spring and fall. Heat pumps with higher HSPFs are more efficient than heat pumps with lower HSPF ratings.
ERV and HRV – Energy Recovery Ventilation or Heat Recovery Ventilation – These are basically the same thing, they are a type of air exchanger. Today’s homes sometimes are built so well that there is not enough natural exchange of interior air, these systems exchange interior/exterior air without dramatically reducing energy loss.
ASHRAE– American Society of Heating, Refrigerating and Air-Conditioning Engineers This is an international technical society organized to advance the arts and sciences of heating, ventilation, air-conditioning and refrigeration.
I hope this explains some of the confusing terms of our industry and will help you in making an informed decision when choosing HVAC systems. I have included links to the Wikipedia definitions for further information.
Fesmire Heating and Air Conditioning Systems 719-240-5109
Serving South and Eastern Colorado including Pueblo, Colorado City, Walsenburg, La Junta, Fowler, Manzanola