A digital thermostat can control the heater and air conditioning (AC) unit in a building, replacing standard analog heater thermostats present in older homes. Among the advantages of switching out the old unit for a new digital model are convenience and savings in the form of a lower energy bill.

Standard thermostats are commonly mounted on a wall in a convenient location where they monitor the room’s air temperature. They are set by adjusting a pointer over a specific temperature along a dial. The thermostat will only trigger the heater on if the temperature in the room falls below the setting. Once the heater comes on, it will stay on until the room warms back up to the setting. At that point, the thermostat turns the heater off.

It’s quite easy to replace an analog thermostat with a new digital model. The old unit is typically held to its mount by one or two screws. Before uninstalling it, switch off power to the unit at the main circuit breaker panel. After removing the screws, wiring coming through the wall to the unit will need to be disconnected and reconnected to the new digital thermostat. The number of wires will vary depending on attached equipment. Be sure to follow all instructions carefully, connecting the correct leads to the correct posts, including the ground wire.

An air conditioning specialist installs, maintains, and repairs heating, air conditioning, and refrigeration systems and may work in commercial or residential settings. These specialists are sometimes referred to as heating/ventilation/air conditioning repair (HVACR) technicians or air conditioning technicians. 

An air conditioning specialist may acquire training from on-the-job experience, an apprenticeship, or through a formal training program. Diagnosing problems, maximizing overall operational efficiency, conducting equipment inspections, and determining fuel or energy consumption is an important part of this job. In order to effect repairs, service contracts and conduct maintenance on various systems, an air conditioning specialist needs to possess some specialized skills and certifications.

Ongoing training to keep up with the ever-changing technology associated with modern air conditioning, heating and ventilation systems is essential for an air conditioning specialist. Some state and regional authorities require licensure, which involve learning the latest information and passing a written test, for air conditioning specialists. 

Some specialists have acquired additional certifications that indicate various levels of competence in handling specialized equipment. For example, special certifications is required for handling anything that uses natural gas or a high pressure boiler. An air conditioning specialist may also be required to pass an examination and gain certification to learn the proper handling of refrigerants.

 

An evaporator coil is a vital part of any heating or cooling system. It is usually found in an air conditioner, because it is particularly good at absorbing heat when air is passed through it. These coils look like a series of pipes. A furnace, central air conditioner, or other air-modifying device passes the household air through the coil, which absorbs the air’s heat and sends it back into the house as cold air via a series of air ducts. The two main components of an air conditioner are usually the condenser and the evaporator coil.

Convection cooling is any transfer of heat that occurs from a movement of fluid. Both liquids and gases can exhibit convection cooling, and the effect can be natural or forced. Natural cooling occurs from heat transfer due to changes in density of the fluid, such as hot air rising and cooler air sinking. Forced convection occurs when any external force is added to move the fluid, such as a fan moving air or a spoon stirring a liquid.

A correct balance between the suction and discharge pressure ensures that the system is healthy and functioning correctly. This relationship, along with the suction and discharge temperatures and the specific refrigerant used, play an important role in determining the correct refrigerant charges for individual systems.

Suction pressure refers to the pressure of the refrigerant at the point where it enters the compressor after leaving the interior of the building. Measured when the compressor is running, this pressure will typically be in the region of 100 pounds per square inch (PSI). The exact suction pressure an air handling unit is designed to produce is a product of the intended capacity of the system, the specific components employed, and the refrigerant the system is designed to use.

A common way to measure the energy-efficiency of an air conditioning unit is through the seasonal energy efficiency ratio (SEER). The more energy-efficient an air conditioner is, the higher its SEER rating will be. Defined mathematically, this rating is the amount of cooling output, measured in British Thermal Units (BTUs) during a typical cooling season, divided by its energy usage, measured in watt-hours, during the same cooling season. As energy prices have increased, the importance of energy efficiency in air conditioning, and therefore that of the SEER rating, has increased significantly.

An air conditioning diffuser distributes air from a home cooling system into each room of the home. The diffuser fits into the walls or ceiling at the end of the air conditioning duct, and serves as a vent for cooled air to enter the room. Each occupied room requires its own air conditioning diffuser, though some smaller areas may share a single diffuser. While these devices appear relatively simple, they must be carefully selected to suit the size and design of the home's cooling system.

Properly-sized air conditioning diffusers maximize the effectiveness of a building's cooling system. This not only improves occupant comfort, but eliminates issues with drafts or humidity in many cases. By making the cooling system as effective as possible, diffusers also help to keep cooling bills low and improve overall energy efficiency. A well-chosen diffuser also reduces noise created by the air conditioning system operation.