Family & Locally Owned. Carson City, Dayton, Gardnerville, Reno and Surrounding areas.     (775) 297-4337

Air Quality

Ask Dirk: My allergies are killing me! How can I reduce allergens in my home?

If you suffer from allergies, you might view spring with mixed emotions. Yes, it will be warmer and sunnier. But those conditions cause plants to grow and bloom, and pollen from those plants can be a problem for allergy sufferers.

Dog with allergiesWhat are we dealing with?

Northern Nevada is a beautiful place to live, but it is rich in allergens. Airborne pollens from rabbit brush, sagebrush, ragweed, and dozens of other plants can cause discomfort like sneezing, wheezing, coughing, itchy eyes, stuffed-up noses for allergy sufferers. In addition, you, your family, your pets, and visitors all bring allergens with them when they enter your home.

How can I avoid allergens?

While there’s not much you can do about allergens when you are outdoors, you can take steps to minimize them in your home.

Infiltration is a significant contributor to poor indoor air quality. Open doors and windows, pet doors, poor sealing of the building envelope, and leaks around registers are prime offenders. But remember, not all allergens come from outdoors. Pet dander, dust mites, mold, and other sources of allergens may already be inside your home.

A properly maintained HVAC system can help in removing these allergy-aggravating substances from the air. The addition of free-standing air cleaners may work even better, especially if your HVAC system isn’t designed to provide extra-clean air.

What can I do?

Remember, the HVAC system only filters when it is moving air. If you are not running central air conditioning in the summer, you may be able to set the fan to “on” if the system allows. This could increase your electric bill as well as accelerated wear on the blower motor.

You’ll want to choose a filter that collects more of the microscopic spores and other pollutants that may aggravate your allergies without stressing the system. Restricted airflow caused by filters that are designed to improve air quality can make the blower motor work even harder, so make sure you select the correct filters and change them regularly. Your service technician can help you choose the best filter for your system.

How will I know what filter to choose?

Filters are rated by the Minimum Efficiency Reporting Value (MERV rating), and range from a value of 1 to 20 http://www.mechreps.com/PDF/Merv_Rating_Chart.pdf. Flat panel filters, installed by most furnace manufacturers, have a 1 to 4 MERV rating. Medium efficiency filters with a MERV rating of 5 to 13 are the most common types used in home HVAC systems. High efficiency with a rating of 14 to 16 MERV, are considerably more expensive, and should only be used in systems designed for them.

No matter what filter you choose, remember to replace it as directed on the packaging. Some homes require filters to be changed monthly at a minimum. If the filter is very dirty when you change it, replace it sooner next time.

What else can help?

Your ducts may also contribute to the problem. Duct leakage can occur over time, allowing dirty air from the attic or the crawlspace to enter the system. Increased pressure in these spaces can also cause that dirty air to leak in around the registers. If you suspect this is happening, have the system inspected by a professional, who will seal any leaks found.

The bottom line

Your first line of defense in reducing allergens in your home, next to a free-standing air cleaner, is regular filter changes with a good quality filter. It’s also a good idea to have your HVAC system inspected on an annual

basis to prevent any problems before they occur.

# # #

Have a question for Dirk? Send it to dirk@roperHVAC.com and he’ll try to answer it in an upcoming column.

2019-05-09T15:51:46-07:00May 9th, 2019|

Ask Dirk: Do I need fresh air in my home?

A Nevada Appeal reader reached out to me with a question about the need for fresh indoor air. Since it’s a great topic for all of us during windows-closed season, I’ve shared my response here.

If you are worried more about air leaks causing your energy bills to soar, the U.S. Department of Energy (www.energy.gov) provides information on DIY home energy audits. If you’re just wondering if you need fresh air in the house, in a word, the answer is yes, you need fresh indoor air in your home. The question becomes, how does it get in besides opening windows?

Fresh air

Ironically, leaks in the building envelope provide fresh air to the home. A certain amount of fresh air needs to come into the home to keep the air healthy; however, a well-sealed home is too tight, and doesn’t leak enough, to provide the needed fresh air.

That can be remedied with a heat-recovery ventilator or an energy-recovery ventilator. This provides two important benefits.

First, you control the source of the fresh air that comes into your home. Rather than air leaking in through cracks and crevices, with some coming from the crawlspace and the attic (not my favorite sources of fresh air), air comes in through a duct from a place you choose for fresh air.

Secondly, it’s more energy efficient than just bringing outside air in. Indoor air that is exhausted passes through a heat exchanger, conditioning the outside air being brought in.

Pressurization

I’m a fan of maintaining a slight positive pressure inside the home. In this situation, air will leak out through the various places that it currently leaks in. So now you’re bringing air into your home from a source that you’ve chosen, and reversing the flow so that air now “leaks” out into your crawlspace and attic, instead of leaking in from those places. Depending on your situation, this can be accomplished by adjusting airflow through a heat-recovery ventilator or an energy-recovery ventilator, by bringing outside air into your return air duct, or a number of other approaches.

Duct leakage

Need more fresh air in my home

If your home is like the majority of homes in our area, your return air runs through the attic. The blower in the furnace pulls air through the return ducts, creating low pressure in them. Improperly sealed joints in the ducting allows attic air to be drawn into the ducting and it is subsequently distributed through your home.

Your supply ducts are most likely in your crawlspace. Here the duct leakage adds positive pressure to the crawlspace, which helps force air from the crawlspace into your living space (often through gaps around the heating registers in your floor).

Ducts that aren’t stretched tight, or that turn corners without proper technique, create more positive pressure in supply ducts, and negative pressure in return ducts, making the aforementioned issues more pronounced.

Other air losses

Kitchen hoods, bathroom fans, and clothes dryers exhaust air from your home, significantly increasing the rate of infiltration. If they are seldom run or run for short durations, this may not be a huge problem. Providing make-up air when these exhaust sources are running can significantly improve the situation, though.

Improving the quality of your air

Depending on where the air is coming from, higher quality filters in your central heating and cooling system can help improve indoor air quality. Care must be taken not to overdo this. Filters that remove more particles from the air also restrict airflow. Whether the filter is in the ceiling or at the furnace, it can decrease the airflow and create extra wear-and-tear on your system.

You can also supplement filtration efforts through the use of high-quality, free-standing portable air cleaners.

If all else fails and you’re still worried about fresh air, open a window for a bit. You’ll feel better.

— Dirk

If you have a question for Dirk, send an email to dirk@roperhvac.com and we’ll try to answer it in an upcoming column.

2019-01-04T14:30:56-07:00December 29th, 2018|

Ask Dirk: 7 Reasons Your Air Filter May Not Work Correctly

Indoor air quality researchers tell us that particulate matter (PM), or particulates, which are invisible pieces of stuff floating around in the air, are bad for human health.

Particulates that are 2.5 micrometers (0.0000025 m) or smaller, abbreviated PM2.5, are worse than larger particulates because they can penetrate deeper into the lungs and more easily find their way into your blood. The biggest sources of PM2.5 in most homes are outdoor air that finds its way into your home, indoor smokers, and regularly burning candles or incense.

Opening windows or using local bathroom and kitchen fans may help dilute particulates, although if the wind is blowing or the pollen count is high, open windows may not help. Another approach is to filter these smallest particulates out of your indoor air using the heating and air conditioning system. Even using a forced air HVAC system, filtering the air may not be helping your indoor air quality. Here are seven reasons your HVAC filter may not be working efficiently.

Not enough runtime

Filters can clean the air only when air is actively going through them. For most people, that’s only when your furnace or air conditioner is running. The rest of the time, air cleaning is not happening.

One option is to put the fan switch on the thermostat in the “on” position instead of “auto.” This will work in some places, but at the cost of higher energy bills. Depending on the equipment you have, it’s possible to add $30, $40, or even more to your monthly electric bill.

Not enough flow

Clean filters - change often

A clean filter is a good filter.

Not enough flow may also be caused by ducts and filters that are too small. That increases something called “total static pressure” in the system, which reduces air flow. Not changing filters often enough also can result in high pressure and low air flow.

Air that can’t be filtered

Sealing your home to lower infiltration can help. Air that leaks in around doors, windows, around floor registers, and from other sources will bring particulate matter into your home. There is no way to filter air that infiltrates, so prevention is the cure.

No filter

No filter means no filtration. Maybe someone removed the filter because it’s difficult to reach or took it out and forgot to replace it. Without a filter, you also could be getting your duct work, blower, air conditioner coil, furnace heat exchanger and other components dirty.

Filter bypass

Installing a deep media filter that’s capable of filtering out the small particulates only functions if properly installed. If it isn’t, air coming into the system will go around the filter, instead of through it.

Improperly sealed ducts

While improperly sealed ducts can waste 20 percent or more of your heating and cooling, they can also cause dirty indoor air. This is especially true of the return air duct that takes air from your living space back to your furnace. In our area, these ducts are typically in the attic. They have lower pressure inside them since the furnace is sucking air through them, so leaks allow air from the attic (not especially nice air) to be sucked into the ducts. If your filter is in your furnace, some of the debris will be caught, but if it’s in your ceiling return air grille, air that’s sucked in from the attic will be delivered straight into your home without the benefit of filtration.

Low efficiency (MERV) filter

The standard rating system for filters is Minimum Efficiency Reporting Value, or MERV. The higher the number, the more particulates are filtered out. Typical one-inch filters are around MERV 2.

Increasing your filter to at least MERV-10 will remove about half of the small particulates. A MERV-13 will remove more than 90 percent of that small particulate matter.

Use care when switching to higher MERV filters, they can restrict air flow, which can decrease your system’s efficiency and life expectancy. As always, filters in your HVAC system should be changed at least quarterly. Your technician can help you select the best filter to meet your needs, balancing the decision between air cleaning ability and keeping your equipment healthy.

2019-01-04T14:38:45-07:00November 7th, 2018|

Ask Dirk: Should I humidify my home?

Living in Nevada, we are very familiar with the concept of low humidity, but what is it, really?

Humidity refers to the amount of water vapor in the atmosphere. Relative humidity, a term used by weather forecasters, measures the actual amount of moisture in the air compared to the total amount of moisture that the air can hold. An important factor in determining how much moisture air can hold is its temperature – colder air holds less moisture than warm air does.

Nevada’s low humidity

Here in Nevada, we often hover around 20 percent for relative humidity, so it feels dry because our air is holding one-fifth (or less) of the moisture it is capable of holding.

Winds along the west coast typically blow west to east which brings cool air (which holds less moisture) from the cool water onshore. Additionally, the Sierra Nevada blocks much of the moisture coming in from Pacific storms.

Home humidity
Since cold air holds less moisture than warm air does, there is less moisture in the air during winter time. To make matters worse, when humidity levels dip, the ambient air feels cooler and we turn up the heat. A properly sealed home will require less humidification, in addition to added efficiencies for your furnace.

portable home humidifier

If humidity levels in the home dip too low, your furniture and house can deteriorate. Wood floors, furniture and millwork may split and crack, paint could chip and electronics can be damaged. Additionally, dry, cracked skin and dry nasal passages may make it easier for germs and viruses to enter your system.

While you may not actually need a humidifier, it may make your home more comfortable by helping to reduce dry skin, itchy eyes and irritated nasal passages, and by reducing static electricity. Adding a humidifier to your home can remedy low humidity with varying degrees of effectiveness and cost.

Natural Evaporation
Adding moisture to the air is as simple as placing a vessel of water on top of, or next to, a radiator or other air heating system, or hanging wet clothes out on a drying rack or hanging in doorways. This is a very low-tech and low power method; however, the strength and humidity controls are limited and available moisture is dependent on the size of the vessel used or the amount of wet clothes left out to dry. Vessels must be frequently refilled and cleaned.

Portable/Room Humidifier
The most common type of humidifier is a portable one and there are two types: cool mist and warm mist, both of which use a reservoir to hold water. The cool mist uses a wick to absorb the water and a fan blows air through a moistened filter. As the air passes through the filter, it evaporates some of the water into the room. Warm mist humidifiers use a heating element that heats the water before dispersing it into the air. Portable systems are easy to use and they can be moved as needed. However, similar to natural evaporation, control and measure of relative humidity is limited, and the reservoir must be refilled about every 24 hours and cleaned regularly.

Whole House Humidifiers
For the most controllable humidity system, adding a whole house humidifier to your furnace will distribute vapor directly into the heated air and circulate it throughout the house using your normal duct system. The whole house system is the most effective and the most expensive option. With a whole house humidifier, you control humidity levels with a device called a humidistat (like a thermostat). This method has the greatest humidification capacity and provides the most control overall.

If you choose to humidify, remember to keep the unit clean and the water fresh on the portable units. A wise man once said, “Do your research before purchasing anything.” Might have been me, but it’s great advice anyway.

2019-01-04T14:28:56-07:00October 13th, 2018|