A Homeowner’s Complete Guide to Whole Home Air Purification Systems

As indoor air quality becomes an increasingly important concern for homeowners, whole home air purification systems have evolved significantly in recent years.

There is no doubt that one of the lingering effects of the COVID-19 pandemic is that indoor air quality is something no one takes for granted. Our own health and that of our loved ones is just too important.

Everyone deserves clean air to breathe, which is why learning what affects indoor air quality and your HVAC system is a smart investment in your and your family’s health. This guide will help you understand the various options available for your HVAC system and how to choose the right solution for your home.

Start with Basic Air Filtration – Select An Air Filter for Your HVAC System

Everyone should be regularly changing the air filters in their HVAC system seasonally (i.e every three months). This passive way of filtering the air keeps your HVAC system clean and tidy for the most part.

PRO TIP: If you are diligently changing air filters and keeping relative humidity levels in check, your ductwork and HVAC system should be sufficiently clean and should not need to be cleaned. As a result, we don’t recommend duct cleaning very often.

We get a lot of questions about which one-inch, pleated air filters are best. Nearly any brand will capture the largest particulates out of the air (i.e. dust, pollen, dander, bacteria, viruses, mold spores) as long as you continue to replace it regularly. Avoid the inexpensive fiberglass filters that were designed to keep the largest particles out of your HVAC, but do not trap finer particles.

We recommend replacing air filters at least every three months. Some homes may need to replace them more often. The best way to check is to see how dirty or furry they are when you replace them.

We recommend two types of air filters you can purchase for your HVAC system.

One-Inch Pleated Air Filters

We recommend purchasing one-inch, pleated air filters with a MERV rating of 7-11 (good, better) to ensure that your residential HVAC unit will be able to draw enough air through it. These can be located in your supply air vents or within your furnace.

PROS: 

    • Very easy to purchase, even at the grocery store!
    • Many choices and brands. Again, the brand itself matters little.
    • Easy to DIY. Even your teenager can handle it.

CONS:

    • Requires frequent replacement (3 months minimum).
one-inch pleated air filter for your HVAC system

An example of a one-inch pleated air filter we use in our HVAC system.

Premium 4-inch Media Filters

A media filter, is a type of air filter that is about 4-inches thick. This type of filter lasts much longer, so it can be a good buy if you’d like an extra level of filtration or you find it difficult to remember to replace your air filters. 

These cost a little more upfront, and your favorite HVAC technician can bring you one that lasts for a year and install it during your regular maintenance visit. We like the media filters from from Honeywell and AprilAire.

PROS:

    • Better long-term value despite initial higher cost
    • Easy to remove this task from your honey-do list and onto your HVAC company’s list
    • Longer lifespan (up to a year)

CONS:

    • Higher upfront cost.
    • Not as many choices and brands.
    • Placement, professional installation recommended

Add Germicidal UV Light Technology

Add Ultraviolet Lights to Your Indoor Evaporator Coil

No matter what type of filtration system you choose, no solution will capture every possible particulate in the air no matter what the label on the package says.

Why? Your central air conditioning system or heat pump’s indoor coil can become dirty because it is frequently humid. The kind of moldy/bacterial growth that lives here will likely bypass your air filters, too.  Regular HVAC maintenance can take care of it, or you can install germicidal ultraviolet lights within your HVAC system to prevent bacterial growth from forming altogether.

UV Lights such as BLU QR® UV Stick Lights kill or inactivate mold, viruses, and bacterial growth. These types of lights will keep the interior of your HVAC system and your indoor air cleaner. Keep in mind that maintenance on UV Lights will require replacing the bulb every year or two. Even with UV lights, you will still need to continue replacing air filters for best results.

PROS:

    • Much cleaner HVAC system
    • Improved indoor air quality
    • Inexpensive accessory
    • Elimination of mold, virus, bacteria growth on indoor coils

CONS:

    • Requires professional installation
    • UV Bulbs require replacement every 1-2 years

Whole Home In-Duct Air Purification Systems Set a New Standard of Clean

Installing an in-duct whole-home purification system is an efficient solution to actively purify the air.  Best of all, these systems are generally easy for a licensed HVAC technician to install in about an hour depending how your HVAC system is set up.

Again, these air scrubber systems are paired with air filters in your HVAC system for best results.

We have personally used and tested the following three systems in our own homes before we have sold any of these to local customers and it lives up to its clean air promises and found them to live up to their clean air promises.

PROS:

    • Actively purifies the air and indoor surfaces
    • Proven and tested in commercial/industrial settings
    • Meets strict California Air Resources Board (CARB) standards which limit ozone emissions to 0.0050 per million

CONS:

    • Requires professional installation
    • Requires maintenance of cells about every 2 years

Dealing with Humidity: A Critical Component to Indoor Air Quality

Balancing out humidity levels is another factor that affects indoor air quality. In general, we shoot for between 40-60% humidity in our Gulf Coast climate. The Environmental Protection Agency recommends keeping indoor humidity levels between 30-50%. The American Society of Heating, Refigerating, and Air-Conditioning Engineers (ASHRAE), a trade association that sets building standards for energy efficiency and sustainability, has recommended indoor relative humidity should be less than 65% to reduce the effects of mold spores. As of 2019, they now recommend limiting the indoor dew point to 60°F because it prevents water condensation until the air contacts a surface that is cooler than 60°F.

Whole Home Dehumidifiers Combat High Humidity

Too much humidity can cause moldy smells indoors and also feel uncomfortable. If you’ve ever been to the beach when the AC is icy and the moment the air stops, you feel hot – you’ve experienced this effect firsthand. High relative humidity levels in the air explain why it feels uncomfortable indoors.

Even though HVAC systems are effective dehumidifiers if they run long enough, sometimes you live in a home where humidity is difficult to control. A whole-home dehumidifier can be a good solution and give your HVAC system a boost.

We recommend AprilAire’s line of Whole Home Dehumidifiers. They have controls built-in, so they don’t require accessories that can push up the price of less expensive brands. As an HVAC professional, I appreciate that the humidistat is built-in because this makes it easier for us to calibrate it for the homeowner. 

PROS:

    • Improved air quality
    • Greater efficiency and lower utility bills
    • Reduces the strain on your HVAC system, prolonging its life
    • Resolves high humidity issues
    • Integrates into your existing HVAC system

CONS:

    • Upfront cost
    • Another appliance to maintain
    • Professional installation required

Whole Home Humidifiers Address Low Humidity

On the other hand, not enough humidity is not recommended and can be uncomfortable. In dryer locales and frequently during the heating season, HVAC companies can recommend whole-home humidifiers to solve that problem if your indoor air dips under the 30-35% relative humidity threshold.

Extremely dry air can cause discomfort, which feels like dry nasal passages, eyes, lips and skin and static electricity build-up. It can worsen allergies as well. Very dry air can also negatively affect indoor furnishings, furniture, hardwood flooring, pianos, books and paper goods, and fine art.

Steam and evaporative humidifiers are two types of whole-home humidifiers that can be added to your HVAC system. Evaporative humidifiers are located near the furnace and click on when the furnace blows air across a moistened panel to draw in evaporated water vapor into the air. Steam humidifiers boil water and release the steam into your HVAC system to moisten the air.

AprilAire also provides whole-home humidifiers that can help you maintain a comfortable indoor humidity level during the winter.  Because our company operates in West Houston, Texas and Fort Bend County including Katy, Richmond, Sugar Land, and Fulshear, we do not install humidifiers at any time of the year. Reducing humidity is what we do year round!  Trust a licensed HVAC company close to you if you think you might need to humidify your air in the winter.

PROS:

    • Improved air quality and comfort
    • Resolves low humidity issues
    • Automated controls
    • Integrates into your existing HVAC system

CONS:

    • Upfront cost
    • Appliance maintenance needed
    • Professional installation required

How to Choose Systems to Improve Your Indoor Air Quality

A variety of factors come into play when considering which filtration, air purification, and dehumidification/humidification systems will fit you and your home’s needs. Keep in mind that indoor air quality centers broadly around filtering particulates in the air and balancing humidity levels.

Partnering with a local, trusted licensed HVAC company with long-standing service and positive reviews is a great way to begin exploring solutions for improving your indoor air quality.  Local HVAC companies will be looking at these factors:

  • Your home’s size and layout, including square footage, how many levels, and your current HVAC configuration.
  • Your specific concerns, including allergies or other health concerns, humidity, pets, and odors.
  • Your budget requirements so you can account for upfront vs long-term value, maintenance, operating expenses, and warranty.

Hopefully this guide has given you food for thought and questions to ask, if you’ve been wondering how air purification and humidity can be addressed with your HVAC system. If you’re tired of dragging around portable dehumidifiers and air purifiers, a whole home air purification system and possibly a dehumidifer may be the way to go.

Need Indoor Air Purification for Your HVAC System? Trust Terry’s A/C & Heating for Solutions

Indoor air purification can be a puzzle.  If you are having issues with frequent illness, allergies, humidity, or indoor smells you can’t pinpoint. Contact Licensed HVAC contractor and Houston-area native Rob Terry at Terry’s A/C & Heating at 281-495-7830 for expert advice about solutions that will fit your budget to improve your indoor air quality and comfort.

We believe in what we install because we’ve tried all of these products first (minus the humidification systems), so we can advise you on what to expect and will take the time so that you understand how regular maintenance for your HVAC system and a whole home air purification system can make a long-term difference. If you’re looking for a high-level of concierge service, you’ve come to the right place. Give our Richmond, Texas-based, family-owned HVAC company a try today.