¿Reemplazar su CA? Esta guía lo ayuda a elegir el mejor sistema

¿Es hora de cambiar tu aire acondicionado? El proceso de selección de nuevos equipos HVAC puede parecer complicado. Para muchos, incluso se siente intimidante, como decidir qué tipo de automóvil comprar.

Pero no tiene por qué ser así. Cuanto más sepa sobre las diferentes opciones de HVAC, más probabilidades tendrá de seleccionar un sistema que satisfaga sus necesidades y se ajuste a su presupuesto.

Lo primero es lo primero:¿realmente necesita un aire acondicionado nuevo?

Muchos propietarios piensan que necesitan actualizar su aire acondicionado cuando:

• Sentir demasiado calor en el verano
• No se puede enfriar lo suficiente ciertas habitaciones
• Experimenta alta humedad interior
• Tiene facturas altas de servicios públicos durante el verano y no sabe por qué

Pero ninguno de estos problemas indica necesariamente la necesidad de nuevos equipos. La falta de mantenimiento, los conductos con fugas, el aislamiento inadecuado y las fugas de aire en toda la casa pueden ser responsables de muchos de estos problemas.

En otras palabras, es posible que no tenga un problema de HVAC. Es posible que tenga un problema de rendimiento en el hogar.

Por otro lado, probablemente debas reemplazar tu aire acondicionado cuando:

• Tiene más de 10 años y no funciona como antes.
• El sistema necesita reparaciones costosas y frecuentes.
• Aún tiene problemas de comodidad después de detener las fugas de aire, mejorar el aislamiento y/o sellar los conductos.
• Tu sistema actual se descompone por completo

Cuando dos o más de los anteriores son ciertos, el reemplazo probablemente tenga más sentido que sonreír y aguantar con un equipo viejo y tosco.

Paso 1:Dimensione el sistema correctamente.

Ok, está seguro de que la única forma de optimizar la comodidad y la eficiencia es reemplazar su aire acondicionado. ¿Por dónde empiezas?

Puede ser tentador solicitar presupuestos para un nuevo sistema que sea del mismo tamaño que el actual, pero en realidad no es una buena idea. Para empezar, es muy probable que haya estado usando un acondicionador de aire de gran tamaño todo el tiempo. Reemplazar una unidad de gran tamaño con otra unidad de gran tamaño no ¡resuelve tus problemas de comodidad!

Para evitar el sobredimensionamiento, cada contratista que le cotiza un nuevo sistema debe realizar un cálculo de carga Manual J en su hogar para determinar el tonelaje apropiado para su nuevo aire acondicionado. Las reglas generales para su zona climática y los pies cuadrados de su hogar no serán suficientes. Si su sistema actual es demasiado grande, ¡esas reglas generales "confiables" podrían ser las culpables!

Another reason to perform a load calculation is that the attributes of your home might have changed since your last HVAC upgrade. Maybe you sealed up some air leaks, increased attic insulation, or otherwise improved your home's energy performance. If that's the case, you might get by with a smaller AC than before.

Long story short:The Manual J load calculation is necessary. Any HVAC contractor who says otherwise is not the contractor for you.

Step 2:Understand SEER.

When it comes to efficiency, nearly any air conditioner available today will be more efficient than what you're replacing. A unit's SEER, or "seasonal energy efficiency ratio" where a higher number indicates a more efficient unit, can help you understand how efficiently a particular AC will operate.

But only to a point. You see, using SEER alone to determine your AC purchase decision is problematic.

For one thing, 14 SEER is the minimum these days. If you're replacing an old system, you're automatically getting an enormous efficiency boost, no matter what! What's more, a unit's SEER only speaks to one aspect of a system's overall efficiency.

SEER reflects the efficiency of an air conditioner while it's operating , and that's important. But it doesn't reflect how you use the system in your home.

Step 3:Prioritize your air handler/furnace selection over SEER.

The type of furnace/air handler, or blower, you choose is more important for efficiency and comfort than an air conditioner's SEER. Now that you understand the basics of SEER (higher number =better), consider the benefit of prioritizing air handler type over SEER for your next air conditioner.

Let's say you're looking at two different systems:

• 16 SEER air conditioner with a single speed air handler
• 15 SEER air conditioner with a variable speed air handler

Of the two, the 16 SEER unit with the single speed air handler will actually lead to less comfortable conditions than the 15 SEER unit, even though the efficiency rating is higher. It might even be more expensive to operate.

¿Por qué? When a variable air flow system is cooling your home, it removes 3 to 4 times more moisture than a standard system with on/off air flow. Basically, you'll feel more comfortable at higher temperatures. You'll also spend less on energy, even though your system has a lower SEER.

A single speed air handler also costs more to operate than an air handler that runs more continuously. It's quieter. It allows for better filtration and indoor air quality. It's just better!

Opting for a thermostat with dehumidification control in addition to a variable speed blower is a great way to further mitigate comfort deficiencies and temper a system's tendency to cycle on and off. It turns the system on via a humidity call, running at a lower speed for longer intervals to better dehumidify the home. Installing one also functionally increases your unit's SEER. For instance, a 14 SEER unit with dehumidification control actually operates at around 15 SEER.

Here's the bottom line:If your budget allows for either a higher SEER or a variable speed air handler, use your money for the air handler. The specs aren't as efficient, but the way it operates will save you money and increase comfort.

Step 4:Opt for a higher SEER.

If you've chosen a variable speed air handler and still have money in your budget, now's the time to get the highest SEER you can afford for an outdoor unit. After making the optimal air handler selection, a unit's SEER really starts to make a difference.

Speaking of outdoor units…

Step 5:Decide among single stage, two stage, and variable speed compressors.

By now, you've identified a properly sized system and decided to prioritize air handler speed over SEER when choosing equipment. What's next?

This is the point at which you choose a compressor type. You can opt for a single stage, two stage, or variable speed compressor. Single stage is the least expensive (and least efficient) and variable speed is the most expensive (and most efficient).

If you've already decided to opt for a variable speed air handler and you have the budget for a two stage or variable speed compressor, that's the way to go. You want your system to cycle as infrequently as possible! Two stage and variable speed compressors already have high SEER by default, so you're set when it comes to efficiency.

Basically, settling for a single stage compressor with a single speed air handler gives you a system that cuts on and off all the time . It's like owning a car that only travels at 0 mph and 65 mph with nothing in between.

Even at 20 SEER, that's not an ideal arrangement.

When choosing a new AC, following the proper sequence makes a difference.

To recap, here are the proper steps to follow when selecting new air conditioning equipment:

• Size the system properly: Performing a Manual J load calculation (or having your contractor perform one) is the only way to go.
• Understand SEER, but know its limitations: A higher SEER is more efficient, but the way an AC operates matters more than its SEER.
• Prioritize air handler type over SEER: If you've got the budget to purchase an AC with a higher SEER, consider a variable speed air handler instead.
• Choose according to SEER: After opting for a variable speed air handler, SEER starts to make a big difference in overall system efficiency.
• Choose a compressor type: Two stage or variable speed compressors are the most efficient options and provide the most consistent comfort. Assuming there's room in your budget, choose one of these compressors over a single stage unit.

By adhering to the above sequence, you won't fall victim to many common pitfalls of AC replacement. You'll end up with the most effective, properly sized system for the money.

You'll probably lower your utility bills, too.