How home cooling works

How home cooling works

With another hot summer clearly upon us in Arlington, TX and North Texas, here is a closer look at how home cooling works and the types of air conditioners that are available.

In an upcoming post, we’ll take a look at home cooling numbers, a few Did You Know Facts, and offer insight on ventilation, maintaining your air conditioner, and common AC problems.

How AC Works

Air conditioners transfer heat from a home’s interior to the outside. It’s as simple as that. It’s not the reverse: cooling warm air inside the home.

The essential parts and what they do include:

  • Evaporator: cooling coils remove heat and humidity from the air using refrigerant
  • Blower: a blower, or fan, circulates air over the evaporator, dispersing the chilled air
  • Condenser: hot coils release the collected heat into the outside air
  • Compressor: a pump that moves refrigerant between the evaporator and the condenser to chill the indoor air
  • Fan: a fan blows over the condenser to dissipate the heat outside
  • Filter: located in the AC unit, the filter removes particles from the air
  • Thermostat: a control system to regulate the amount of cool air that is distributed

Split Systems

Many types of air conditioning systems are called split systems because they are made up of an outdoor unit, which contains the condenser and compressor, and an indoor unit, which is often connected to a furnace or heat pump.

A majority of the homes in Arlington, TX are split systems, which require service and maintenance from a heating, ventilation, and air conditioning (HVAC) contractor for everything from installation to routine servicing, maintenance, and repair.

There are many basic things homeowners can do easily to make sure their heating and cooling equipment is performing optimally and efficiently, requiring fewer service calls from local HVAC contractors.

Types of Air Conditioners


A central air conditioner, found in the majority of Arlington, TX homes, circulates cool air through the home using a system of ducts and registers.

Life span: 15-20 years with proper service and maintenance

Cost: $$$

Choosing Your AC: Central air provides the most even cooling throughout the home. If ductwork is already in place and is in good shape, replacing an aging AC unit can be a cost-effective option to conserve energy and save money, assuming you are upgrading to one of today’s energy-efficient models.

Pro: Central air conditioners are mostly quiet (unless the outdoor unit is underneath a bedroom window) and operate more efficiently and effectively than window units.

Con: Can be more expensive to install if you do not have the ductwork already in place. Central units require more attention from homeowners, including changing filters (no big deal), to requiring semi-annual checkups, to requiring service and repair from professional technicians from Arlington, TX contractors.

Tip: If ductwork is already in place have a service tech make sure it is sealed properly and connected without sags or excessive bends.


Room air conditioners are actually the most popular cooling system. They provide spot cooling and can be either a window or portable air conditioner.

Life span: 10-15 years

Cost: $

Choosing Your AC: If you do not have an air conditioner, a room unit can provide cooling to select places in the home at an affordable cost. Room air conditioners may also be a good option to cool “trouble” rooms in the home (that are not easily cooled) or locations (like garages or workshops) that are expensive to add on to existing cooling systems.

Pro: Inexpensive way to cool a room or addition to your home. Most room air conditioners do not need professional installation or servicing, although there are exceptions.

Con: Improper installation can result in significant air leakage, increasing it by as much as 10 percent.

Tip: Install rigid form panels in between the window frame and unit and secure with duct tape instead of accordion panels to reduce air leakage.

Ductless, Mini-Split

Ductless, mini-split air conditioners are mounted on a wall and provide zoned cooling without the ductwork.

Life span: 12-15 years

Cost: $$$$

Choosing Your AC: Ductless mini-split systems can provide cooling and well as heating. They are highly efficient, work in all climate zones, and can be an affordable alternative to installing a ducted system, depending on your environment and needs.

Pro: Easy to install and avoids energy loss associated with ductwork

Con: Is expensive — in homes with existing ductwork, a mini-split can cost 30 percent more in energy costs than adding an air conditioner unit to the existing system.

Tip: Keep the compressor (the part of the unit that is outside the home or in a basement, which we do not see many of in Arlington, TX) clean to prevent overheating.

Evaporative Cooler

An evaporative cooler is also called a swamp cooler. It cools outdoor air using evaporated water and circulates it throughout the house. These are not typically found in Arlington, TX, Fort Worth, and Dallas.

Life span: 15-20 years

Cost: $$

Choosing Your AC: If you live in an arid climate (not Arlington, TX, Fort Worth, and Dallas) an evaporative cooler can be a cost-effective cooling option. In addition to cooling air, they add moisture, which increases occupant comfort.

Pro: Costs about half as much to install and uses about a quarter of the energy of a central air conditioner.

Con: Requires more frequent service and maintenance on the part of the homeowner and is better suited for areas with low humidity in the cooling months.

Tip: Clean regularly and drain evaporative cooler to ensure it operates as efficiently as possible.

Tips for Lower Cooling Costs

  • Install and set a programmable thermostat — it can help you save 10 percent on heating and cooling costs a year
  • Use a ceiling fan — they allow you use raise the thermostat setting by four degrees without impacting your comfort
  • Insulate your attic and walls and seal cracks and openings to prevent warm air from leaking onto the home or cool air to escape
  • Don’t heat the home with appliances like the stove on hot days — consider using an outdoor grill instead of an oven
  • Install energy-efficient window coverings that let natural light in and prevent solar heat gain