_{The most recognized standards for HVAC design are based on ASHRAE data. The most general of four volumes of the ASHRAE Handbook is Fundamentals; it includes heating and cooling calculations. Each volume of the ASHRAE Handbook is updated every four years. The design professional must consult ASHRAE data for the standards of design and care as the typical building codes provide little to no information on HVAC design practices; codes such as the UMC and IMC do include much detail on installation requirements, however. Other useful reference materials include items from SMACNA, ACGIH, and technical trade journals.}
SEER is related to the coefficient of performance (COP) commonly used in thermodynamics and also to the Energy Efficiency Ratio (EER). The EER is the efficiency rating for the equipment at a particular pair of external and internal temperatures, while SEER is calculated over a whole range of external temperatures (i.e., the temperature distribution for the geographical location of the SEER test). SEER is unusual in that it is composed of an Imperial unit divided by an SI unit. The COP is a ratio with the same metric units of energy (joules) in both the numerator and denominator. They cancel out, leaving a dimensionless quantity. Formulas for the approximate conversion between SEER and EER or COP are available.[34]

Although your AC may continue to work for a time, if you ignore warning signs of air conditioner repair troubles, it can be much more costly to repair in the long term. Diminished cooling capacity not only makes your home uncomfortably warm, but it also raises your utility bills significantly as your unit struggles to maintain the desired temperature ineffectively. A system put under strain is likely to overheat, resulting in major damage. Therefore, it is best to have your air conditioner repaired promptly when you discover signs of trouble. 

Natural ventilation is the ventilation of a building with outside air without using fans or other mechanical systems. It can be via operable windows, louvers, or trickle vents when spaces are small and the architecture permits. In more complex schemes, warm air is allowed to rise and flow out high building openings to the outside (stack effect), causing cool outside air to be drawn into low building openings. Natural ventilation schemes can use very little energy, but care must be taken to ensure comfort. In warm or humid climates, maintaining thermal comfort solely via natural ventilation might not be possible. Air conditioning systems are used, either as backups or supplements. Air-side economizers also use outside air to condition spaces, but do so using fans, ducts, dampers, and control systems to introduce and distribute cool outdoor air when appropriate.
_{If your AC doesn’t turn off when room temperature reaches the temperature set on the thermostat, the problem is generally occurring either at the thermostat or in the electrical system that runs the outside condensing unit. You can use the AC’s circuit breaker to shut off the unit, but that should not be a permanent solution—circuit breakers are not designed to be used like light switches.}
When seeking emergency heating or cooling services you want experts that actually care about the results and your comfort. You want to choose the HVAC company in Alexandria with extensive skill and top-class tools, but you don’t want them to take advantage of your bad situation! With HVAC & Plumbing Unlimited, you never need to worry. We make it our mission to offer superior services any time you need it, and we guarantee cost-efficient solutions that restore your comfort.

At Horizon Services, we strive to provide all of our customers with the peace of mind that comes from knowing that you have a skilled team on-call for any AC emergencies that may arise. We have more than 300 fully stocked trucks ready to go at a moment's notice. Our Horizon technicians undergo rigorous training, including a mandatory 150 hours of training every year, to ensure that they're always up to date on the latest techniques and HVAC technology. Plus, we perform extensive background checks, including drug and criminal checks, on all of our employees so you don't have to worry about letting a stranger into your home when your AC breaks down in the middle of the night. When you're dealing with an air conditioning emergency, trust the experts at Horizon Services!