The right cooling system helps your home stay cool and comfortable, while the incorrect system not only leaves you sweating, but also consumes energy and wastes money. Two-stage air conditioners promise greater energy efficiency and operation compared with conventional single-stage systems, resulting in increased comfort and lower energy bills. While many of the most efficient air conditioners on the market rely on two-stage or variable speed technology, the possible issues related to two-stage systems could mean they might not be the best choice for each homeowner.
Single vs. Two-Stage Overview
A single-stage air conditioner includes one compressor rate. The unit is either switched on and running or switched off completely, with nothing in between. Two-stage systems feature two compressor speeds, with one often put at 60 to 70 percent of their maximum. Approximately 80 percent of this moment, the machine runs in the lower rate, but about the hottest days, it switches to a greater rate to beat the heat. Since they are usually running in a lower rate, they are inclined to run for extended periods, decreasing the starts and stops that burn energy.
Higher Costs
As a result of their more complex technology, two-stage systems cost more than single-stage on average, based on Qualitysmith.com. This added cost can make two-stage systems hard to warrant in smaller residences or milder climates, where single-stage systems may cool the house just as efficiently.
Complex Repairs
The typical residential air conditioner at the U.S. is determined by just a single compressor rate. Two-stage air conditioners represent a newer, more complex technology using a larger number of parts. This means these systems could be more challenging to fix and maintain, and it could be harder to come across a trained technician equipped to manage this more complex technology.
Real-World Performance
The efficacy rating of an ac system is often listed using the seasonal energy efficiency ratio, with greater values related to more efficient processes. In general, two-stage systems offer higher SEER values than single-stage units. A 2006 study released by the American Council for an Energy Efficient Economy found that the greater SEER values on two-stage systems tend to be unrealized under real-world operating conditions. While the analysis states that single-stage units tended to perform very near their advertised SEER, two-stage units examined in the study functioned in just 59 to 84 percent of advertised SEER. This discrepancy tended to be the greatest in leaky homes, those who have oversize cooling system, and residences where the fan is permitted to run constantly, even if the air conditioner isn’t running.