Proper Sizing for Your Portable AC
Finding the best remedy means the first fact you must know about portable air conditioners is proper size. In this context, “size” equates to cooling capacity, not physical dimensions. Standard capacity ratings are expressed as BTU levels of 5000, 7000, 9000, or 12000 BTUs. “BTU” is short for “British Thermal Unit,” a scientific term that denotes relative rate of heat removal. However, you don’t have to comprehend the technical elements, just a single number that corresponds to cooling power.
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I always suggest that prospective buyers overestimate maximum cooling capacity for intended use. Most HVAC experts advise customers to get the “proper” size instead of too much power. The underlying rationale is that oversized ACs cool faster and thus complete more cycles. That in turn leads to less total operating time and higher recirculated air humidity. In short, their reasoning is that ACs should run longer for more air dehumidification.
The flaw in that theory is the fact that more than volume or square feet must be calculated to determine BTUs accurately. Many other factors like insulation R-value, vent distribution, air currents, and exterior construction material must be considered. Since very few HVAC “experts” account for those variables, many homes have uneven interior heat distribution.
While trying to find the ideal portable air conditioning unit, keep in mind that you must battle potent UV rays in addition to heat emitted by the sun. Thus, slightly more power is better than too little. At the outset, my standard advice is always against buying any model with a maximum capacity of 5000 or 7000 BTUs. Neither category has adequate power to cool any area larger than a tiny room. Indeed, many smaller rooms with full-sized windows may even be too hot for such units, due to extra warmth of UV rays.
The Best Portable AC Units
My recommendation is either a 9000 or 12000-BTU air conditioner. Although the latter is preferable, it also has a higher price tag. Thus, 9000 BTUs strikes the best balance between cost and cooling capacity. Never forget that since portable ACs are designed for mobility, you must calculate BTUs by largest possible space to be cooled.
Level of energy consumption is the last feature to take into consideration about portable air conditioners. Although it might seem that lower BTUs equate to less power consumption, there are exceptions. After all, a 6.2-liter Corvette with a V8 engine can go up to 30 miles on a single gallon of gasoline – about the same distance as tiny 4-cylinder subcompacts.
The buzz word is efficiency. Narrow down your choices to models with equal energy efficiency ratings or energy consumption levels, or both. If those figures are not revealed, they typically are not worthy of consideration anyway. My experience is that 12000-BTU models are more efficient than a lot of 7000-BTU analogues.