Installing an air filter in your HVAC ductwork is the best way to achieve clean, breathable air for your entire home. A tight building envelope insulates a modern home well, improving temperature control. However, it contributes to more concentrated indoor pollution. The good news is various options can compensate for this; we’ll explore a few if you’re looking for an air filter replacement or upgrade.
Residential HVAC filters are available as media filters, which provide a physical barrier to trap particles. Meanwhile, electronic filters capture various particles and contaminants via a high-voltage electric charge. Some filtration solutions combine both methods to improve their effectiveness.
A whole-house filter differs from the air filter installed in your furnace or air handler unit. It is typically placed in a return-air duct. From here, it traps particles before they enter the return airflow of a forced-air heating or central AC system. Unlike traditional AC filters, a whole-house air filter must be installed professionally.
A built-in filtration system can serve as a whole-house purifier. As long as your HVAC fan is on, it constantly filters the air that passes through. The effectiveness and longevity of a filter depends on the type. These are the most common air filters for HVAC ductwork in homes:
Matted fiberglass filters are often found in forced-air furnaces. They’re designed to capture large dust particles before they enter ductwork and other crucial components. However, the smallest microscopic particulates can pass through. These are major culprits of respiratory irritation, so depending on your home and whether you have allergies, asthma, or other issues, these filters aren’t always the most effective.
Fiberglass filters are good at keeping large particles out of sensitive HVAC components. However, they typically don’t have a Minimum Efficiency Reporting Value (MERV) of over 4. This means their overall particle filtration ability is relatively low.
An extended media filter is a stacked set of filtration materials. The filtration media is set in an 8-inch-thick accordion-like pile. While pleated filters with cotton or polyester folds are a step up from fiberglass filters and have MERV ratings of 5 to 8, extended media filters can have a greater range of filtration power.
But these filters aren’t for a DIYer. They require a professional to install in line with your ductwork within a specialized filter holder. The initial installation can cost $400 to $600, according to This Old House. However, the filter needs replacement only once a year, which generally costs $60 or less.
An electrostatic precipitator is a hi-tech option that also integrates into ductwork. It creates static electricity, which most people prefer to avoid. Instead of making your hair frizzy and causing annoying shocks, the high-voltage current helps trap particles, which take on an electric charge so a collector plate can attract them like a magnet.
Electrostatic precipitators effectively catch extremely small particles, like smoke particles and most allergens. Another advantage is they never have to be replaced, although the aluminum collector plates must be cleaned every few months. The plates can be cleaned off by rinsing them in soap and water.
An electrostatic filter often includes a flat or pleated carbon filter to improve efficiency.
Instead of static electricity, electronic filters produce a high-voltage charge generated by a transformer. An electronic filter is a mechanical air filter that plugs into an outlet. It won’t work if your HVAC system has a return grille filter. Nonetheless, MERV ratings of 8 to 16 mean they’re highly effective at filtering small particles. The higher upfront price tag is offset by the need for duct filter replacement only about once a year.
Electronic filters are generally safe and effective. However, when shopping around, look for third-party testing data on any product you consider. The filter should use an ionizer process similar to a whole-home air purification system and not generate ozone, which can be a health hazard.
High-efficiency particulate air (HEPA) filters come in many forms. Some fit inside air handlers, while others are designed for ductwork. They remove 99.97% of airborne contaminants. These include tiny dust, pollen, and smoke particles as well as pet dander, mold spores, and bacteria. Whether you suffer from allergies, asthma, or other respiratory issues, a HEPA filter can eliminate the tiny particles that trigger your symptoms.
A built-in UV filter uses ultraviolet light to kill microorganisms, including bacteria and viruses. Short-wave UV light effectively neutralizes organic contaminants in the airflow. However, a UV filter does not remove dust and other particulate-based pollutants. Therefore, UV and HEPA filters are often combined into the same unit. Research your options before choosing one, as some filtration systems produce ozone from oxygen molecules.
Less commonly used in homes, gas-phase filters use gas sorption to attract gas molecules to a solid surface. They effectively remove odors and volatile organic compounds (VOCs). An activated carbon and charcoal media is used but a short lifespan means the filter must be replaced frequently. Also, it only removes gaseous pollutants and is ineffective against other particulates; therefore, gas-phase filters are typically used as an add-on filtration option.
Every air filter has a MERV rating, which ranges from 1 to 16 and measures a filter’s ability to capture particles. The higher a filter’s rating, the more effectively it traps particles and the more expensive it is.
Higher-rated filters can also reduce airflow and reduce an HVAC system’s efficiency. Therefore, filters with MERV ratings of 8 to 13 are recommended for homes. Your HVAC contractor can help find the best option for your system.
A standard HVAC filter fits in a slot above, below, or on the side of the air handling unit. Ductwork filters are placed in a return air grille in a wall or ceiling, just inside the vent. Or, they can be installed somewhere between the return duct and the air handler.
A small HVAC system may require just one filter. If you have a two-story home, it probably has two air filters (one for the upstairs HVAC system and one for the downstairs system). An additional filter may be needed for an indoor air quality solution like a whole-home mechanical ventilation system. An add-on ductwork filter provides additional filtration, so your heating and cooling system may have multiple filters.
A pleated filter at least 3 inches thick with a high MERV rating is often considered an ideal solution. However, various factors help determine the best HVAC filter for your home. Some of these considerations include:
Lastly, the filter’s size and design must fit your HVAC system. If not sized correctly, a filter can let air escape around its sides. This counteracts its benefits and allows contaminants in.
We provide indoor air quality services, including whole-house air purifier installation, for homeowners in the The Greater San Francisco Bay Area area. From thorough inspections to high-quality workmanship, we have you covered. Our ductwork filters and air purification systems capture dust, dust mites, pet dander, VOCs, germs, smoke, mold spores, and odors. Check online for special offers to help you save. For a consultation and a ductwork filter replacement or upgrade by trained professionals, call (415) 223-1647 today.
A few attic and crawl space insulation options are available. Poor insulation can reduce your comfort and cause you to spend more on heating and cooling. But the best type depends on your home. We’ll look at the most common types of attic insulation and insulating materials best suited for crawl spaces so you can make an informed decision.
Insulation prevents drafts and the transfer of heat and moisture. Since heat naturally rises, the attic is one of the most important areas to insulate. Each type of insulation has pros and cons and is not suited for every situation. These are the top choices, although the best depends on your needs, budget, and local climate.
Spray foam is the only liquid-based insulation. It has many benefits, including ease of application. The material is sprayed into place, where it thickens and grows, filling any gaps or spaces where heat can escape. It forms a durable, airtight seal.
An insulation’s R-value measures its ability to resist the movement of heat (the higher the number, the better a material’s thermal performance). Spray foam has an R-value of 5.6 to 8, which makes it an effective insulator. Other benefits of using it include:
The higher cost of spray foam insulation is offset by its energy efficiency. Precautions are recommended during installation; a mask, respirator, and goggles should be worn. The materials in the foam can irritate your skin. We suggest letting a professional install spray foam insulation, as they understand the complexities involved.
Rigid foam boards are great for insulating basements and are preferred for crawl space insulation. They are suited for insulating foundation walls. Sealing the joints between the boards prevents air passage, while rigid foam:
Available in standard sizes, foam boards are easy to cut to fit. This usually requires a circular saw and masonry blade, but sometimes a utility knife can be used to score the material; then you can snap it apart. It’s also easily attached with screws or a special adhesive. Smaller pieces can be sealed with caulk or spray foam.
The types of foam board insulation include:
The most common type of attic insulation, fiberglass batts have a recognizable pink cotton candy or cloud appearance. They consist of tiny glass fibers produced via heat from recycled material and sand. The fibers are rolled into large sheets fused by a chemical vapor.
The benefits of fiberglass batt insulation, and why it’s such a popular option, include:
While many people don’t need a professional to install fiberglass batt insulation, it doesn’t come without risks. The glass in the material can cause injury, while the vapor from the barrier can be harmful (wearing gloves and a mask protects you from harm).
Other downsides to this insulation include reduced performance if it gets wet. Fiberglass batts take a long time to dry and can breed mold after absorbing moisture. The insulation is also attractive to rodents and other pests.
Blown-in fiberglass insulation is also available. The base material is the same as with batts (without the vapor). It is installed using a blowing machine. In addition, blown-in fiberglass insulation provides an airtight layer, filling cracks or gaps to limit the movement of hot or cold air. It also has sound-insulating properties.
Other perks include:
This attic insulation is also applied using a blowing machine. It consists of recycled wood, cardboard, newspapers, and other materials, which are made flameproof with boric acid and other substances. Blowing the material in fills spaces and gaps in attic walls.
Blown-in cellulose is eco-friendly; no new material needs to be produced and it can be reused. It also has a 23% higher R-value than fiberglass batts. Wind-washing is reduced as well. This phenomenon is when insulation is pushed away from the edges, which reduces thermal performance.
These advantages help offset cons such as messy installation. The cellulose should also be kept dry. Any dampness can allow mold to grow. Such a situation takes much time and effort to resolve, as the insulation must be cleaned up bit by bit.
The best insulation to choose depends on where you’re installing it. Foam boards are best for crawl spaces. Also, think about how you’re using the space. Consider properties such as the type of material, its thickness, insulating value, sound absorption, energy efficiency, and ability to control moisture. However, if you intend to turn your attic into a living space, you may want to insulate the roof instead.
The level of heat resistance you need depends on your home’s location and climate. The U.S. Environmental Protection Agency (EPA) has established eight climate zones across the country. The recommendations for insulation efficiency in an attic, floor, etc. vary depending on the zone you live in. Generally, the farther north you live, the colder your location, and the higher in altitude you are, the higher the R-value you’ll need.
Signs your home is under-insulated include a sudden increase in energy bills, meaning your HVAC system is working harder. Cold spots, especially near windows and doors, can mean air is leaking through cracks or seams. Hearing lots of noise from outside can mean your walls and ceilings need to be better insulated.
When it comes to attic and crawl space insulation, there are a few ways to consider your options. Choosing the right insulation requires knowledge of available materials and your home. We can install various types of insulation to regulate indoor temperatures. Our team can also help you take advantage of moisture control, sound dampening, and energy savings as well as insulation rebates, coupons, and tax credits. Call (415) 223-5096 to learn more and request help with crawl space and attic insulation.
Most HVAC pros suggest replacing air filters every 3 months; it’s the most basic form of AC maintenance. Can you afford to wait longer than 90 days? This depends on a few factors, such as the type of filter, system usage, and your household. There are many reasons to consider changing your filters more frequently. We’ll examine reasons not to wait as long and how to know a filter has gone bad.
Air filters don’t last forever. You don’t want to wait too many months past your filter’s life expectancy, or else repair issues and high energy bills can become problematic. Whether you replace your filter every month or 90 days depends on the following:
Visually inspecting the filter is the only way to know if it’s good or needs to be replaced. We recommend checking it monthly (more often if you get a new pet or the outdoor air quality is poor). This way, you can replace a clogged filter in time and figure out how quickly it gets dirty. When inspecting a filter, hold it in front of a light source. The light should pass through; if not, replace the filter with a clean one.
Remember, there’s no strict guideline for how much dirt is acceptable. A filter with a thin layer of dirt may be fine if you can still see its material. If its surface is completely obscured by debris, replace the filter. A musty odor also means you need a new filter.
Other than seeing a dirty filter, other signs it may need changing include:
The longer you wait, the more dust, dirt, and allergens will collect on the filter. Your HVAC system will work less effectively, reducing comfort, energy efficiency, and indoor air quality. A buildup of mold, fungal, and bacterial particles can damage the system or cause health issues in your household.
Also, a thick coating of dirt can impede airflow, which increases wear and tear on your heating or cooling system. Dust can jam fan motors, valves, and other moving parts. The excess strain can lead to frequent repairs. Over time, strained components can fail, causing others to break down, until you’re dealing with a major issue like compressor failure.
Over time, if you don’t change the filter as recommended or schedule routine AC maintenance, your HVAC system can be damaged. Replacing the filter won’t fix the problem at this point. Call an experienced contractor if you notice signs such as:
We are a leading air conditioning service company in the The Greater San Francisco Bay Area area. Whether you need a new filter, a tune-up, or an AC repair, our licensed and trained technicians are committed to customer satisfaction and a job well done. Our team is prompt and ready to ensure your home stays comfortable. They can fix any issue with your HVAC system and provide annual AC maintenance to prevent breakdowns and improve efficiency. To request routine service or repairs, call (415) 223-1647 today.
Everyone benefits from cleaner air, but it can come at a price. The cost of a whole house purification system can range from $400 to $4,000 (in 2024 dollars), according to HomeGuide. However, the exact amount you spend on installation depends on the following:
In this guide, we’ll look at all these factors. It can help you budget for a whole house purification system that meets your household’s indoor air quality needs.
The cost of central air purifiers varies considerably. The national average is $1,300, but you can spend just a few hundred dollars on a low-end system.1 Meanwhile, a high-end system can cost several thousand dollars. Why is there such a difference? To answer this question and help you understand how whole house purification systems are priced, here are the factors to consider:
A purification system is generally defined by the type of filter it includes. The cheapest type is a single-function system, while multi-stage systems that remove the smallest particles are the costliest. Here are the average costs of the most common whole-house air purification systems:
Many companies make whole-house air purifiers. Prices vary significantly from one brand to another. For example, brands such as Field Controls, Honeywell, and Reme Halo tend to cost less than higher-end names like Carrier, Trane, and Lennox.
Each brand may offer various options at different price points. Shopping around can help you find an affordable solution. Look for products with Energy Star certification. Efficiency is important as the system must run constantly to achieve and maintain good indoor air quality.
Also, try to find equipment covered by a long-term warranty. This requires installation by a licensed contractor but can result in savings on service over the system’s life.
Higher-efficiency filtration systems cost more. However, you must weigh the benefits of having one, such as relief from allergies and respiratory issues. If your pets shed a lot, a high-efficiency whole house purification system can remove excess hair and dander.
Whole-house HVAC filters are rated using a Minimum Efficiency Reporting Value (MERV). The most common ratings for air filters include:
The larger a home, the more powerful an air purification system it will need. A large house may also require multiple filtration units, as can one with multiple levels or an open floor plan. An installer must consider your home’s size, layout, and other features before determining the ideal type of system. The larger and more complex it is, the more it’ll cost to purchase and install.
Labor charges can add significantly to the cost of a whole-house purification system. With labor included, a whole-house HEPA system can cost $4,000. An extended media air filter or UV filtration system can cost up to $800 (installing a hybrid UV/mechanical filtration system can cost up to $3,000). Combining equipment and installation costs, an electronic filter can cost as much as $2,000.1
However, the total cost of installing a whole house purification system is determined by more than the price of equipment and labor. These are some other variables to consider:
At TRIO Heating, Air & Plumbing , we install innovative, high-quality air purification systems in The Greater San Francisco Bay Area area homes. We offer seamless installation and also provide filter replacements and air duct cleaning. Our experienced team is committed to improving your home’s indoor air quality. To learn more about whole house purification systems and inquire about costs and special offers, book an appointment with us or call (415) 223-5615.
You can delay or avoid thermostat repair with proper maintenance. A well-maintained thermostat generally lasts about 10 years. Although one of the least expensive HVAC components to replace, it’s crucial for reaching and sustaining optimal temperatures in your home.
A thermostat is wired directly to your heating and cooling system. It allows for the temperature to be adjusted and the system to be turned on and off manually or automatically. Therefore, thermostat maintenance should be part of your routine. These are some thermostat maintenance tips to keep it in top shape.
One of the simplest fixes for home thermostat problems is simply checking the batteries. A low battery reduces the amount of power available to your thermostat. This can make it inaccurate and less able to manage your comfort. To avoid these issues, replace the thermostat batteries every six months or as the manufacturer recommends.
Even if your thermostat is hardwired, it may have backup batteries. Change these to prevent disruptions in heating and cooling due to a wiring issue.
One of the best thermostat upkeep practices to get into the habit of is keeping the unit as clean as possible. A buildup of dirt and dust can prevent your thermostat from working properly. Cleaning it every few months can help you avoid HVAC performance issues due to controller malfunctions, and it gives you a chance to look inside and check for other signs you need thermostat repair. Here’s how to clean a thermostat:
Thermostat testing and calibration ensure that the system is accurately reading temperature, allowing it more control over your home’s HVAC systems. If the temperature keeps fluctuating, your energy bills are increasing, or causing HVAC thermostat issues like short cycling, your thermostat may need calibration.
To calibrate a thermostat, first test it by comparing its reading with a dependable thermometer. If the readings differ by more than 3ºF after 20 minutes, check the product manual for how to calibrate the unit. Calibration techniques differ based on the type and model of a thermostat.
When people ask how to maintain a thermostat, one aspect that’s often overlooked is the placement. Constant exposure to high heat can damage a thermostat, so the unit should not be near a heat source, such as direct sunlight, a vent, or an appliance. To protect its integrity and accuracy, it should be mounted on an interior wall in or near a frequently used room. Excess heat can cause inaccurate readings, affect the cycling and efficiency of your HVAC system, and increase the likelihood you’ll need thermostat repair.
Drafts and other temperature irregularities can throw off your thermostat settings. That’s why sealing and insulating the area around the thermostat is essential during installation. This ensures it gets an accurate reading of the temperature in the room instead of drafts inside your walls or elsewhere.
Smart thermostat maintenance has some unique considerations compared to standard models. You can often save yourself hours of digital thermostat troubleshooting simply by resetting and updating the software on your unit. Often, this resolves error codes and any other issues you’re facing.
Don’t wait to see signs of thermostat failure to get help! By prioritizing proactive maintenance at least once a year, you’ll get ahead of potential problems while tuning up your HVAC systems at the same time, ensuring they’re ready to run smoothly all year.

Your indoor air quality has a surprising effect on your thermostat’s accuracy. Part of programmable thermostat care is ensuring the air in your home is clean enough to give an accurate temperature reading. Excess dust, debris, and humidity in your indoor air can prevent the sensors in your thermostat from working properly, which means an IAQ solution can help your HVAC systems run more reliably.
Smart thermostats don’t just offer convenience — they save you as much as 10% a year on energy costs and even extend the lifespan of HVAC systems. These advanced systems offer far better reliability than traditional models, making them well worth the investment.
If the above maintenance tips aren’t solving your thermostat troubles, it’s time to call an expert. Here at Trio, thermostat services are a daily job for us, and our team has the experience to troubleshoot even the toughest issues. Whether you have a smart thermostat or a conventional one, leave it to us to get it working as it should again.
When you work with Trio Heating, Air and Plumbing, bundling thermostat maintenance with indoor air quality upgrades is an easy, affordable way to boost your home’s comfort across the board. Since thermostat service is usually a very quick job, it just makes sense to combine this with other services, such as duct cleaning, air sealing, air scrubber installation, or even putting in a whole-house air purifier.

We provide high-quality thermostat installation, repair, and maintenance in the greater San Francisco Bay Area, CA. Our licensed HVAC technicians can help no matter what type of thermostat repair you need. They can service manual, digital, programmable, and smart models. As part of our Protection Plan, thermostat maintenance is performed during your annual AC and heating system tune-up.
To learn more or book thermostat services for your home, contact us online or call (415) 223-5096.
At TRIO Heating, Air & Plumbing , we’re proudly upgrading our service vehicles to a Tesla fleet. This signifies the principle behind our new slogan: “TRIO: Where Sustainability Meets Service Excellence”. Aside from planting a tree for every job we do (which means a great deal for the region), we’re committed to environmental sustainability and high-quality service in every aspect of our work, down to the vehicles our employees drive.
Until now, we have relied on gas-powered vans. Investing in Teslas is allowing us to convert to an eco-friendly all-electric fleet. Safety is another reason for our initiative. The autopilot feature in Tesla cars adds a new level of protection. It’s one of many features that help reduce accidents; therefore, our sales team and service technicians are safer on the job.
Tesla vehicles are reliable and convenient so our employees can be happy at work, which we know contributes to higher quality service. We also know how much Tesla means in the Bay Area. Here’s a look at the benefits of a Tesla and how it can improve a fleet.
Driving a Tesla doesn’t only improve safety. It has many other perks that benefit casual drivers and businesses. These benefits include:
The system sends smartphone notifications as well. An app lets you view live feeds and speak through a vehicle’s exterior speaker. Or, you can view recorded footage once you return to your car. Additionally, Teslas let you shut off certain features and lock the trunk or glove box remotely, which limits access to them by, for example, valet personnel.
Upgrading an entire fleet may seem like a big investment, but these vehicles have 5-star NHTSA safety ratings in every category. The low risk of injury means our workers are always protected. Their day is also easier. Remote diagnostics and mobile service benefit drivers by saving them time and allowing them to focus on their job duties.
Tesla accommodates all types of drivers. The company’s fleet and business program is designed to help turn your fleet all-electric and reduce your organization’s environmental impact. You can also take advantage of tax incentives to further reduce operational costs, on top of savings on gas and maintenance expenses.
However, Tesla doesn’t only benefit your bottom line. Driving one also benefits the community. With the low probability of accidents and injuries, using features such as Autopilot contributes to safer roads. Therefore, we’re helping keep people throughout The Greater San Francisco Bay Area and the Bay Area safe.
Here’s yet another perk. California permits Tesla owners to use HOV lanes without occupancy restrictions. This allows our sales and service teams to get to work sites more efficiently.
Switching to an all-electric fleet of vehicles is a big undertaking. Since we want to ensure our customers see uninterrupted service, we’re slowly converting from our gas-powered vans to a full fleet of electric vehicles. Taking a phased approach allows us to ensure the process goes more smoothly and our fleet is 100% reliable when it’s complete. Therefore we can continue prioritizing our customers’ needs and the lasting performance of their AC, heating, and indoor air quality systems.
Whether you need help with air conditioning or heating installation, repair, or maintenance, TRIO has you covered. Our sustainability initiatives, including upgrading our gas-powered vans to all-electric Teslas, will allow even faster customer service response times. We can also continue to guarantee the highest quality work and provide the best products and brands on the market.
A professionally trained team ensures your home is comfortable, safe, and energy efficient. Aside from AC and heating equipment, they install and service thermostats, insulate attics and crawlspaces, and provide duct cleaning and sealing. To learn more about these and our air scrubbers and whole-house purification systems, or request service, book an appointment online or call (415) 223-1647.