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Why Join ASHRAE

ASHRAE Membership

ASHRAE membership is open to any person associated with heating, ventilation, air conditioning or refrigeration. ASHRAE is unique because its membership is drawn from a wide range of disciplines relating to the HVAC&R field. Approximately 51,000 individuals from more than 100 nations belong to the Society.

Discounts on Publications

ASHRAE members earn 15% off publications. Hundreds of titles are available including the complete collection of ASHRAE Standards including 90.1, 62.1 and 189.1.
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Develop Leadership Skills

When you join ASHRAE, you are making an investment in yourself. When you become active in the Society by giving your time and sharing your knowledge, you get even more out of that investment.

Network with Industry Professionals

Each month, all over the world, ASHRAE chapters convene for an informational program featuring a speaker or topic that is key to professionals in the industry. Meet with your peers and share ideas.
 
 
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Consumer Center FAQ

What size air conditioner do I need for my house?
What is the recommended indoor humidity level for homes?
My co-workers and I frequently argue about where to set the thermostat in our office. What is the recommended temperature for offices?
What is a BTU?
What is a ton?
What does EER mean? Should I spend more money for a higher EER unit?
What does SEER mean? Should I spend more money for a higher SEER unit?
What does HSPF mean?
What does AFUE mean?

What size air conditioner do I need for my house?
Sizing a residential heating, ventilating and air conditioning (HVAC) unit depends on such variables as geographic location, orientation to the sun, construction details, insulation values, window area and type, etc. Under sizing a system may lead to warmer or cooler temperatures than desired by some occupants. Over sizing the system may lead to humidity or moisture control problems in the space.

What is the recommended indoor humidity level for homes?
A good range is between 30% and 60% relative humidity. You can determine humidity levels with a relative humidity sensor typically referred to as a hygrometer or psychrometer. This level of humidity minimizes the indoor growth of allergenic or pathogenic organisms such as dust mites and molds.1
A wider range of humidity levels, from a low of 25% to a high of about 80%, can be acceptable in terms of thermal comfort (your comfort level) depending on the type of clothing worn and the level of physical activity.2

My co-workers and I frequently argue about where to set the thermostat in our office. What is the recommended temperature for offices?
ASHRAE specifies the combinations of indoor thermal environmental factors and personal factors that will produce thermal comfort conditions acceptable a majority of the occupants within the space (ASHRAE Standard 55-2010, Thermal Environmental Conditions for Human Occupancy.). To be specific, temperatures in the winter can range from 68-74° F and 73-79° F in the summer (from ASHRAE Standard 55-2010, Thermal Environmental Conditions for Human Occupancy.)

What is a BTU?
BTU stands for the British Thermal Unit (Btu). It is a unit of heat energy in the inch-pound unit system, which is common today in the United States. The Btu is defined as the amount of heat necessary to raise the temperature of one pound of water one degree Fahrenheit from 58.5 to 59.5.
A Btu is commonly used to indicate the heating and cooling capacity of a system, heat losses, and heat gains. To give an example of system capacity, a 10,000 Btu window air conditioner is capable of removing 10,000 Btus of heat per hour. To give an example in terms of heat gains, the typical heat gain added to a room by a person at rest is about 230 Btu/hour.

What is a Ton?
A ton is the unit of measurement for air-conditioning system capacity. One ton of air conditioning removes 12,000 Btus of heat energy per hour from a home. Central air conditioners are sized in tons. Residential units usually range from 1 to 5 tons.

What does EER mean? Should I spend more money for a higher EER unit?
EER stands for energy efficiency ratio. The higher the EER rating, the more energy efficient the equipment is. This can result in lower energy costs. The following US Dept. of Energy Web site can show how to calculate potential energy cost savings of a more efficient unit -www1.eere.energy.gov/consumer/calculators/homes.html. The Air-Conditioning and Refrigeration Institute (ARI.org) posts a Certified Ratings directory, which lists EER ratings of various air- conditioning equipment.

What does SEER mean? Should I spend more money for a higher SEER unit?
SEER stands for seasonal energy efficiency ratio. The higher the SEER rating, the more energy efficient the equipment is. A higher SEER can result in lower energy costs. This U.S. Dept. of Energy Web site, www1.eere.energy.gov/consumer/calculators/homes.html, can show how to calculate potential energy cost savings of a more efficient unit. The Air-Conditioning and Refrigeration Institute (ARI.org) posts a Certified Ratings directory, which lists SEER ratings of various air-conditioning equipment.

What does HSPF mean?
HSPF stands for heating system performance factor. The higher the HSPF rating, the more energy efficient the equipment is. A higher HSPF can result in lower energy costs. The Air-Conditioning and Refrigeration Institute (ARI.org) posts a certified ratings directory, which lists HSPF ratings of various air-conditioning equipment.

What does AFUE mean?
AFUE stands for annual fuel utilization efficiency. The higher the AFUE rating, the more energy efficient the equipment is. A higher AFUE can result in lower energy costs. The Gas Appliance Manufacturers Association, www.gamanet.org, publishes a directory of certified AFUE ratings.

Disclaimer: ASHRAE Technical Services Staff responds to technical inquiries and has compiled answers to the following consumer frequently asked questions (FAQs). Answers to consumer FAQs are provided as a service specifically for homeowners and the general public. While every effort has been made to ensure their accuracy and reliability, they are advisory and provided for informational purposes only, and in many cases represent only one person's view. They are not intended and should not be relied on as an official statement of ASHRAE.
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1 ASHRAE Standard 62-2001, Ventilation for Acceptable Indoor Air Quality
2 ASHRAE Standard 55, Thermal Environmental Conditions for Human Occupancy
3 Addendum 55a, ASHRAE Standard 55, Thermal Environmental Conditions for Human Occupancy