A dry bulb thermometer is a device used to measure the air temperature without taking into account humidity or moisture levels. It simply measures the heat energy in the air and is a key tool in HVAC for assessing temperature conditions. It is called "dry bulb" because the thermometer’s bulb is not affected by wetting...

A dry-charged unit is an air conditioner or heat pump that is shipped without refrigerant, containing only a dry nitrogen holding charge to prevent internal contamination. The refrigerant is added during installation, making it compatible with older systems that use R-22 refrigerant. These units were more commonly used when R-22 refrigerant was being phased out,...

An HVAC system feature where two compressors are used in the outdoor unit. Typically, one compressor handles standard cooling demands, while the second compressor engages during higher cooling needs, such as on particularly hot days. This setup improves energy efficiency by using the smaller compressor for lighter loads and enhances performance during extreme conditions, while...

A dual-fuel system is a type of HVAC setup that combines an electric heat pump and a gas furnace. The system is designed to switch between these two heating sources depending on the temperature and operating conditions. The heat pump is typically used when outdoor temperatures are mild because it is more energy-efficient, while the...

Passages in an HVAC system that serve as pathways for air to travel. Ducts are used for both delivering conditioned air (heated or cooled) to different parts of a building and removing stale or unconditioned air. They are typically made of materials like metal, fiberglass, or flexible plastic and are a crucial component of central...

Ductwork refers to the system of pipes or conduits used in heating, ventilation, and air conditioning (HVAC) to distribute air throughout a building. These ducts can be made from materials such as sheet metal, fiberglass, or flexible plastic. Properly designed and installed ductwork is critical for efficiently delivering heated or cooled air to maintain indoor...

DX stands for "Direct Expansion," which refers to a type of HVAC system where the refrigerant absorbs heat directly from the indoor air and evaporates as part of the cooling process. In this system, the refrigerant circulates through coils and changes state (from liquid to gas) as it absorbs heat. This is a more efficient...

An ECM (Electronically Commutated Motor) is a highly efficient and reliable type of brushless DC motor commonly used in HVAC systems. It operates with variable speed capabilities, allowing it to adjust airflow or water flow to match the system's needs more precisely. These motors are often found in high-quality furnaces, air handlers, and boiler pumps....

Ecologic is a term used by Maytag to identify their line of environmentally friendly heating and cooling equipment. This designation signifies products designed to be energy-efficient and eco-friendly, helping reduce environmental impact while maintaining reliable performance.

An economizer cycle is an energy-saving feature in HVAC systems that uses cool outside air to help with indoor cooling. When outdoor conditions are favorable (cool and dry), the system brings in fresh outside air and reduces or eliminates the need for running the air conditioner. This process helps save energy and improves ventilation inside...