Multi-Zone HVAC Systems & Ductless Mini-Splits: How They Work & Pros/Cons for Arizona Homes

Keeping your Arizona home comfortable year-round can get expensive fast. A multi-zone HVAC system can help you contain those costs. They let you heat or cool only the parts of your home you are using at any given time. It is possible to configure a ducted central AC to support zoned operation. However, there is another option: a ductless mini-split HVAC. Here is what they are and how to decide if one would be a good fit for your Arizona home.

What Is a Multi-Zone HVAC System?

A multi-zone HVAC system is a heating and cooling system that divides your home into distinct comfort zones. Each space has its own thermostat, allowing for finer indoor temperature control. If you want a central HVAC system to support zoned operation, it will need a specially designed zoning system. Those include motorized ductwork dampers to segment your HVAC ductwork into self-contained sections. The dampers connect to a controller that communicates with the zone thermostats and your HVAC system. When one of the thermostats calls for heating or cooling, the system turns on your HVAC and opens the appropriate dampers.

Ductless mini-splits are a popular type of multi-zone HVAC. They are an excellent option for homes without preexisting HVAC ductwork. They are also a good option if your home’s ductwork is inadequate or in need of major repairs. Knowing that can help you when you are weighing a mini-split versus central air.

Zoning HVAC benefits include enhanced comfort and reduced operating costs. By limiting heating and cooling to only the spaces that require it, your HVAC runs less often. Conventional central HVAC systems will cost less to run with a zoning system. However, ductwork zoning only delivers maximum benefits when paired with a two-stage or variable-speed HVAC system. Mini-splits, by comparison, offer maximum savings due to their inherent design advantages.

How Multi-Zone Ductless Systems Work

Ductless mini-splits include an outdoor unit similar to that of a central AC. However, a mini-split outdoor unit has its fan on its side rather than its top. They are also usually smaller than a central AC outdoor unit. Some of the largest models feature tall outdoor units, but they remain slim. Mini-split outdoor units also do something central AC units do not: distribute electricity.

In place of a single indoor air handler, multi-zone mini-splits use individual wall-mounted units. They connect to the outdoor unit via refrigerant and power lines. The outdoor unit supplies the electricity each air handler requires to operate. Each air handler has its own thermostat and temperature controls. That is what makes mini-splits capable of zoned operation. You can leave individual units off when appropriate and set custom temperatures for the ones that are running.

Pros and Cons for Arizona Homes

Ductless mini-splits offer flexible installation options. You can install one with a single air handler or one that serves up to eight spaces. Smaller units are perfect for adding cooling capacity to a hot room that your central AC doesn’t cover. You could also use one to cool a home addition, a garage, or a home office. A mini-split can work alongside an existing central AC or replace one entirely.

Cost Drivers + When It Is Worth It

You should know that ductless mini-splits can be somewhat costly. Small models that cool one or two rooms are affordable. However, cooling your whole home with a ductless mini-split requires a much larger system. Those can cost twice as much as comparable central HVAC systems. If you have an especially large home, you may need multiple mini-splits to cover it all. That would significantly increase your upfront costs.

However, the cost of a mini-split may be well worth it in some situations. One is if your home has no built-in ductwork. While that is rare in this part of the country, it is worth pointing out. More commonly, a mini-split may be a better option if your existing ductwork has serious leaks or damage. In those situations, the expense of repairing or replacing your ductwork can make a mini-split more cost-effective.

How to Choose Zones + Sizing Basics

Ductless mini-splits come in the same range of capacities as central HVAC systems. However, choosing the right mini-split isn’t always easy. Improper system sizing is one of the most common AC installation mistakes. With a central system, you can modify ductwork to divide the system output as needed. With a mini-split, you only have specific air handler capacities to choose from. Most mini-split air handlers have capacities ranging from 9,000 BTUs to 36,000 BTUs. You can attach up to eight air handlers in combination, provided they do not exceed the outdoor unit capacity. If there is no easy way to divide the capacity to meet your home’s needs, you may need multiple mini-splits.

Generally, you will need an air handler for each room in your home. If your home has an open floor plan, you may need multiple air handlers to serve larger spaces. Arizona’s climate typically requires about 35 BTUs per square foot. For a 1,500-square-foot home, that calls for a 4.5-ton HVAC system. You can sometimes reduce those needs through upgraded insulation and air sealing. Our HVAC experts can evaluate your home to determine its precise capacity needs. We can also help you decide on the type and number of air handlers to use to support your ductless mini-split zones.

Get a Multi-Zone System Quote from Western States Home Services

If you are interested in a multi-zone HVAC system in Arizona, Western States Home Services can help. As a Carrier Factory-Authorized Dealer, we sell high-quality mini-splits. We can provide both AC-only and heat pump varieties. As a locally owned and operated HVAC company, we have deep roots in Arizona and understand the local climate. We offer financing options on approved credit to help you afford a mini-split. You can also take advantage of the numerous money-saving coupons we offer to help keep your costs low.

Contact our team at Western States Home Services today for a quote on a multi-zone system in Arizona.

FAQs

How loud is a ductless mini-split?

Ductless mini-split air handlers operate without making much noise. Most emit between 25 and 35 dB, which is barely above a whisper. You can expect a mini-split outdoor unit to make between 30 and 38 dB of noise while running.

Are mini-splits as efficient as central AC?

Most ductless mini-splits are more efficient than central AC systems. They offer zoned cooling by default, helping minimize operating costs. There is also less ductwork loss, which can lead to inefficient operation of the central AC.

How do you maintain ductless mini-splits?

Maintaining a ductless mini-split is not difficult. You must wash the air filter in each air handler after every two weeks of use. You should also have your mini-split serviced by a professional once per year.