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Indoor Air Quality
Preventative Maintenance
The Truth About Mold
The Air You Breathe
Comfort by Design
Efficiency and Comfort
Humidity
Professional Organizations
Consumer Information
Indoor Air Quality
According to the EPA, the air inside the average building can be up to five times more polluted than the air outside. Pollen, dust mites, dirt, and mold spores in a building’s air can cause minor health problems like eye and nose irritation, dizziness, and headaches. Indoor air pollution can also cause more serious problems like respiratory illness, as well as aggravate allergies and asthma. There are three ways you can improve the air quality in your building:
Source Control
You can eliminate many pollutants like dust and pet dander by continually cleaning the building. Making sure the heating and air conditioning systems are well-maintained also helps remove pollutants before they reach the building, and cleaning air duct systems may be helpful in keeping your systems maintained.
Improved Ventilation
You can decrease the concentration of indoor pollutants by increasing the quantity of air circulating and with the proper use of an air side economizer and/or exhaust fans can assist with lowering the indoor pollutants, and increase the outdoor ventilation rate at the same time.
Air Cleaners
Well-maintained and efficient air filters can significantly lower the amount of pollutants in the air. Their usefulness varies considerably, depending on the type of filter and on the strength of the indoor pollution source.
Contact me to find out which methods are best for your building. For more information, read The Inside Story: A Guide to Indoor Air Quality , and the EPA’s Basic Information about Indoor Air Quality .
Preventive Maintenance
Preventive Maintenance = $avings!
Take care of your HVAC system, and it will take care of you.
Preventive maintenance agreements (PMAs) are agreements between you and your Air Conditioning Contractors of America (ACCA) quality contractor for scheduled inspections and maintenance of your heating, ventilation, and air conditioning (HVAC) system.
PMAs are generally scheduled quarterly, with a annual preseason service in the spring and fall to maintain peak efficiency, help keep utility bills lower, extend the life of your HVAC system, and avert failures. Sometimes PMAs are referred to as “planned maintenance agreements,” “start and checks,” or “preventive service agreements.” Most agreements offered by ACCA contractors cover an inspection of the entire HVAC system and routine maintenance (such as replacing or cleaning filters).
Energy Consumption
The HVAC system is most likely the single biggest use of energy in a building. In commercial applications where refrigeration is applied (combined with the HVAC systems), huge amounts of energy are used in the building. In fact, over a third of the energy used in the United States is used to heat and cool buildings.
According to the Consortium for Energy Efficiency (CEE), up to 50% more energy can be saved with proper installation, sizing, and maintenance of commercial central air conditioning and heat pumps.
Out of Sight, NOT Out of Mind
The cliché “out of sight, out of mind” is often the reason for neglected maintenance on HVAC systems. HVAC systems are usually installed where they aren’t seen, such as in a section of the basement, on rooftops, or in mechanical rooms, making them easy to ignore. The systems are simply taken for granted, until they fail. Decreased efficiency, utility overpayment, discomfort, loss of productivity, premature replacement, and higher repair costs are the result.
Getting your HVAC system checked a least twice annually is just as important as changing the oil in your car every 3,000 miles!
What should you expect your ACCA member service technician to do during a PMA visit?
Spring Visit (preparation for summer season)
What’s your bottom line?
Savings: PMAs typically more than pay for themselves through higher efficiency, lower utility bills, and contractor discounts. PMA customers typically receive a discount on all parts and services performed during the entire year.
Peace of Mind: Predictive maintenance will mean fewer system failures and a longer life for your HVAC equipment.
Priority Service: Should a system failure occur during the heat of the summer or the cold of the winter, customers with PMAs generally receive priority service.
Continuity: Many ACCA contractors assign technicians to specific customers. That way, you get to see and know the same service technician, and he or she becomes more familiar with you and your equipment.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
The Truth About Mold
There's Good Mold and There's Bad Mold
Molds are the “bleu” in bleu cheese and Roquefort. Molds improve our wine. They produce penicillin and antibiotics and are used widely in the food and beverage industry. Without mold and mold’s decaying mechanism, the natural environment would be overwhelmed with large amounts of dead organic matter.
Despite many harmless and beneficial molds, some molds can be toxic and pose health threats to humans. The Environmental Protection Agency (EPA) cautions that all molds can cause health problems under the right conditions. The word “toxic” refers to mold that produces hazardous compounds, or mycotoxins.
Often included in the list of toxic molds is Stachybotrys Chartarum, a greenish-black mold, which can grow on high-cellulose, low-nitrogen materials such as fiberboard, drywall, paper, dust, and lint – all of which are found in buildings – when these materials become wet.
There is evidence that mold exposure can cause the following symptoms:
Mold is a natural byproduct of the fungi family that thrives when organic substances and water combine under certain circumstances. Mold reproduces via spores that can remain dormant, yet viable, for years. They “come alive” again in the presence of moisture.
HVACR mechanical systems are not generators of mold; their metallic surfaces do not provide the organic matter mold needs to grow. However, systems that are not well maintained could support mold growth. It's important that your system:
The first step is to alert your HVAC contractor and the builder (if the building is relatively new) regarding your concerns. The contractor or builder will inspect for mold. If there is mold, the next step is to identify its type and establish whether it’s toxic. If so, evacuation, abatement, and remediation may be necessary.
The identification of mold requires specialized testing and laboratory analysis. Partly because of media attention to mold issues, mold abatement has become a growth industry, often attracting less than reputable people who may cause more harm than good by not identifying toxic mold, improperly removing it, or charging you for work you don’t need. Check with your state environmental protection or public health agency to find out if mold remediation contractors are required to be certified and licensed.
ACCA member contractors are concerned about the quality of the air you breathe, too, and many have added indoor air quality services to their offerings. If your HVAC contractor does not perform mold analysis, abatement, and remediation, he or she may be able to refer you to a reputable company that is a trained and certified in this kind of work.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
The Air You Breathe
What's in your air and what can you do about it
Unfortunately, in today’s world, pollution is everywhere. And with the type of cleaning products, manmade goods, and activities undertaken within homes and buildings, indoor environments can become very uncomfortable. Even “fresh,” outdoor air has as many as 30 million dust or pollutant particles per cubic foot.
There are, however, measures you can take to lessen the effects of these particles in your building. Since the building is essentially an enclosed system, heating, ventilation, air conditioning, and refrigeration (HVACR) contractors are able to tackle pollution head-on by moving the air through a high-efficiency air cleaner.
What does an air cleaner do?
At its most basic level, an air cleaner filters out the particles that cause irritation, such as pollen, spores, dust, and other contaminates. In order for any air cleaner to work correctly, the particles need to pass through it. Hence, if the particles are not in the air stream (for example, they’re dust on furniture), an air cleaner won’t remove them. However, a good air cleaner will:
A good air cleaner reduces or removes the irritants that cause allergic symptoms. You may choose a portable air cleaner for smaller spaces or a whole-house air cleaner that works in conjunction with your forced-air system to provide cleaner air throughout your building.
What kinds of residential air cleaners are out there?
There are basically two: furnace-mounted, whole-house units and portable single-room units. Both types of cleaners have different models with varying methods of cleaning the air and capacities for doing so. Your dwelling may help determine the right unit for your needs. A room air cleaner may be best in an apartment, for example, while a whole-house unit might work better with a furnace and air conditioning system. It’s important to note that both room and system air cleaners come in a variety of models, and that not all models use the same technology to clean the air.
Each kind of air cleaner has its pros and cons, which may differ depending on your air-cleaning requirements. Take a look at what your needs are based on your dwelling and allergies and talk to your professional HVACR contractor about the best kind for you.
What are the most effective air cleaners?
Media Air Cleaners
These units use high-efficiency pleated filters, or “media,” to remove about 99% of larger particles, including many allergens. With irritants in the spore and pollen range, they are as effective as HEPA filters but not as effective in filtering out the super-small particulates such as bacteria, viruses, and respirable dust. Media air cleaners are cost effective compared to HEPA filters because the filters are usually less expensive and generally need to be replaced only every one or two years.
HEPA Air Cleaners
HEPA (High Efficiency Particulate Air) cleaners also use high efficiency pleated media to remove particles. To be designated HEPA, an air cleaner must remove 99.97% of all particles 0.3 microns in size (such as dust and mold spores). Due to high cost, operational complications, and other problems, HEPA units are usually seen in residential applications as one-room, portable units. When media in these units need to be replaced, it’s often relatively expensive to do so. Some require charcoal filters that need to be cleaned frequently. Warranties for HEPA cleaners are normally one to three years.
Electronic Air Cleaners
There are two types of electronic air cleaners. Both electrically charge particles and attract them to a collection material. The standard electronic air cleaner will collect charged particles on a specially designed “plate.” Most electronic cleaners can obtain 95% efficiency or higher on various particles when the collection plates and ionizing wires are clean, but they can lose some efficiency as they collect dirt.
A newer technology in electronic air cleaners is called “electronically enhanced media” combining elements of both electronic and media air cleaners. Particles are electrically charged and then collected by the massive air cleaning media of a traditional high-efficiency cleaner. Because the replacement of the media is simple and there are no plates to clean, efficiency is maintained throughout the media’s life. Electronically enhanced media air cleaners are 99% effective in the removal of numerous particle categories. Electronic air cleaners generally have warranties of one to five years.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
Comfort By Design
by Jim Herritage, CEM
Before you replace your heating, ventilation, and air conditioning (HVAC) system, there are some things you should know. The first is that a quality installation begins with a professional design.
Most of us don’t think about “design” when we think of heating and cooling, but it’s just as important as a solid architectural design. A professional HVAC contractor won’t simply replace what you have now with new equipment. It’s possible that your existing system wasn’t sized properly to begin with!
To make sure your new HVAC system meets your needs for comfort and energy efficiency, a quality contractor performs a series of calculations that take into account the overall climate where you live; how your building is sited (for example, if it faces south or north); the amount and quality of insulation in walls, basement or crawl space, and attic; how many windows the building has and how efficient they are; other sources of ambient heat, such as kitchen appliances and lights; even landscaping near the house. These are called “load calculations.” The formulas, which are included in ACCA’s Manual J®, were developed by HVAC experts at ACCA and are the industry standard, often incorporated into local building codes.
Turn to the pros
Why should you care about load calculations? It’s simple: an under-sized system can reduce the comfort of your building, use more energy, and not last as long as a properly sized system. An over-sized system will cost more than you need to spend and may contribute to moisture-related problems down the line.
Any contractor who tells you a load calculation isn’t important is not a professional. The professional understands that your year-round comfort is the ultimate goal. In the summer, your air conditioning system not only cools your building’s air (sensible cooling), it removes moisture (latent cooling). In the winter, your heating system must keep you comfortable without causing high utility bills.
The right equipment
The load calculation also enables the contractor to select the right kind of system. Heating and air conditioning equipment comes in many capacities, configurations, and efficiencies. It’s important that your contractor selects the equipment that will be compatible with your building’s heating and cooling needs.
Ducts, grilles, and registers
A qualified contractor will make sure the duct work in your building is the right size and insulated properly. Properly installed and maintained duct work can last twenty years or more, but time, heat, and humidity can degrade the ducts’ insulation. In addition, ducts may have collected contaminates over the years and need to be cleaned out.
Tell your contractor if some of the offices in your building have been too hot or too cold, as this could be a sign that the ducts are the wrong size or are dirty. The contractor will evaluate the amount of air each office should get and verify that your duct system is clean and configured to deliver the right air to the right office.
Your return air grilles and supply air registers play an important role in providing heating and air conditioning comfort, too. There are times when simply replacing one or more of these devices can cause a noticeable improvement in your building’s thermal comfort.
Return grilles that are undersized can reduce the efficiency of the air conditioning system as well as the comfort in your building. Your contractor will verify that these devices are sized and operating properly and may make suggestions for improved performance.
Select a professional
Buying a new comfort system is a major expense, and most building owners replace their heating and air conditioning systems only every ten or twenty years. It just makes sense – and cents! – to choose a contractor who knows how to design, install, and service the right equipment for you. Using a professional contractor assures you that your building will be comfortable for many years to come.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
Efficiency & Comfort
Tips for Maximum Efficiency and Comfort
Are you getting the most for your comfort dollar? Or are you paying to heat and cool the neighborhood?
Whether your comfort system is old or new, in a new or old building, a multi zoned or a single zoned building, there are many little things you can do to optimize its efficiency and minimize your utility bills. They’re definitely worth the small amount of time and expense they take, because in the long run, they’ll save you money.
Outside
Whatever the season, you want to keep your comfortable air inside the building. That means caulking and weather stripping doors and windows, around chimneys and flues, and anywhere else inside air can escape.
Inspect the exterior of your building once or twice a year. A good way to remember is to do it when you have your regular, professional HVAC check-up because heating and cooling will be on your mind anyway.
Keep vegetation and debris well away from the outdoor unit of your system. They can block air flow, which forces the system to work harder to produce the same level of comfort. You’ll spend more now … and in a few years, when the equipment fails prematurely and you have to replace it.
Inside
Set the thermostat at the highest comfortable level in the summer and the lowest comfortable level in the winter. A change in one degree changes energy consumption by about 4%. Humidifiers and dehumidifiers can make a huge difference in how the temperature feels.
Install a programmable thermostat. It will automatically adjust the temperature at night or when you’re not going to be building for a long period of time.
Lights are a source of indoor heat, a problem in the summer. Wherever possible, replace incandescent bulbs and fixtures with compact fluorescents. They use a lot less energy, produce less heat, and last longer. Today’s fluorescents aren’t like those of only a few years ago – you can choose a warm, yellow light similar to incandescent light. You can use them in table lamps, ceiling fixtures (including ceiling fan fixtures), torchieres, and for indoor and outdoor lighting. Some can be used with dimmer switches, too. Avoid halogen lamps. The light is clear and bright, but they create a lot of heat.
In the summer, keep blinds closed on the sunny side of the house during the day. In the winter, open them to take advantage of solar heat but close them at night to help block cold air (even if you have insulated windows).
Insulate attics, crawl spaces, basements, and walls to the R value recommended for building area. Your HVAC contractor can tell you how much you need. Don’t forget to insulate duct work in un-conditioned space.
HVAC System
Check filters regularly and clean or replace them when needed. Your HVAC technician will tell you how often that’s likely to be based on the manufacturer’s recommendations and local air quality conditions.
Make sure room vents are working properly. Close them at least part-way in rooms you’re not using. Never block them with furniture, pictures, or window coverings.
Consider a zoned system if your building two or more stories or areas. A programmable thermostat in each zone can save energy and money.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
Humidity
It’s All Relative
Proper humidity levels keep you healthier and more comfortable.
Your heating, ventilation, and air conditioning (HVAC) system can do more than heat and cool your building. It can also keep the humidity at a comfortable level in winter and summer. It’s a delicate balance: if it’s too low, you’ll feel the effects of colds, respiratory infections, and asthma more, and some of the furnishings in your building will literally dry out. If it’s too high, you’ll be uncomfortable but mold and mildew will flourish. They love moisture!
HVAC systems balance temperature and humidity. The best person to design a system appropriate for your climate and your comfort needs is a professional ACCA member contractor. He or she understands the science of your building and applies the principles contained in the ACCA design and technical manuals to the design, selection, and installation of an HVAC system that’s right for you.
ACCA manuals are the industry standard, often incorporated into local building codes and endorsed or recommended by the Department of Energy, the Environmental Protection Agency, and equipment manufacturers.
Relatively Speaking …
Relative humidity (RH) is the percent of moisture actually in the air compared to the maximum amount of moisture the air can hold at that temperature. Cold air can hold less moisture than warm air. At 70ºF, air can hold as much as 12 times the amount of moisture as 10ºF air. That’s why it’s usually more humid in the hot summer months.
Winter Humidification
Most heating systems just heat the air, changing the temperature, not the humidity. Cold air is dry, and forced-air systems and heat pumps pull outside air for heating. When 10°F outside air is heated to 70°F, the humidity level in your building will be the same as the outside air’s, around 7%. That’s one reason your skin feels dryer, perhaps even chapped, in the winter. So in dry cold climates, you will probably want to add a humidifier to your heating system.
The effects of bacteria, viruses, fungi, respiratory infections, allergic rhinitis and asthma, and ozone production during the winter can be minimized by higher humidity levels. Studies have shown that wintertime levels of 68°F/60% RH are just as comfortable as 72°F/30% RH; so by increasing the RH and lowering the temperature, you will minimize negative effects while lowering your utility bills.
Because the outside air temperature and RH can change in a short time, even a few hours, a computer-controlled humidifier is probably your best choice. It will automatically adjust for these fluctuations to provide enough moisture for a healthy, comfortable building and minimize or prevent window and cold surface condensation.
Summer Dehumidification
Air conditioners pull moisture from the air (HVAC professionals call that “latent heat,” as opposed to “sensible heat,” the temperature) as they cool it, which is one reason you feel better in an air conditioned building. If they didn’t, you’d feel cold and clammy instead of cool and comfortable. In particularly hot and humid climates, however, you may need to augment the dehumidifying capacity of your system.
Very high moisture levels give you that “sticky” feeling and may lead to health problems resulting from the growth of bacteria, viruses, fungi, dust mites, and mold. Air at 78°F/30% RH provides the same level of comfort as does 74°F/70% RH air. In the summer, turning the thermostat up lowers your utility bills, so dehumidifying can save you money as well as add to your comfort.
Although your air conditioning system or stand-alone dehumidifier is designed to remove moisture and decrease the RH levels in your building, in very humid areas of the country, it may not be capable of lowering the levels below 60% RH. In such cases, your ACCA quality contractor may suggest alternative or additional equipment and control strategies.
It’s Your Choice!
The choice is yours: a comfort and health indoor air system, or a furnace/boiler and an air conditioner. Since more than a third of your time is spent in your building, it is important to make the right choice.
© Air Conditioning Contractors of America Association, Inc., www.acca.org. Reprinted with permission.
Preventative Maintenance
The Truth About Mold
The Air You Breathe
Comfort by Design
Efficiency and Comfort
Humidity
Professional Organizations
American Society of Heating, Refrigerating and Air-Conditioning Engineers
Air Conditioning Contractors Of America
North American Technician Excellence
Plumbing-Heating-Cooling Contractors Association
Consumer Information
The Inside Story: A Guide to Indoor Air Quality
Basic Information about Indoor Air Quality
A Brief Guide to Mold, Moisture, and Your Building
Indoor Air Quality
According to the EPA, the air inside the average building can be up to five times more polluted than the air outside. Pollen, dust mites, dirt, and mold spores in a building’s air can cause minor health problems like eye and nose irritation, dizziness, and headaches. Indoor air pollution can also cause more serious problems like respiratory illness, as well as aggravate allergies and asthma. There are three ways you can improve the air quality in your building:
Source Control
You can eliminate many pollutants like dust and pet dander by continually cleaning the building. Making sure the heating and air conditioning systems are well-maintained also helps remove pollutants before they reach the building, and cleaning air duct systems may be helpful in keeping your systems maintained.
Improved Ventilation
You can decrease the concentration of indoor pollutants by increasing the quantity of air circulating and with the proper use of an air side economizer and/or exhaust fans can assist with lowering the indoor pollutants, and increase the outdoor ventilation rate at the same time.
Air Cleaners
Well-maintained and efficient air filters can significantly lower the amount of pollutants in the air. Their usefulness varies considerably, depending on the type of filter and on the strength of the indoor pollution source.
Contact me to find out which methods are best for your building. For more information, read The Inside Story: A Guide to Indoor Air Quality , and the EPA’s Basic Information about Indoor Air Quality .
Preventive Maintenance
Preventive Maintenance = $avings!
Take care of your HVAC system, and it will take care of you.
Preventive maintenance agreements (PMAs) are agreements between you and your Air Conditioning Contractors of America (ACCA) quality contractor for scheduled inspections and maintenance of your heating, ventilation, and air conditioning (HVAC) system.
PMAs are generally scheduled quarterly, with a annual preseason service in the spring and fall to maintain peak efficiency, help keep utility bills lower, extend the life of your HVAC system, and avert failures. Sometimes PMAs are referred to as “planned maintenance agreements,” “start and checks,” or “preventive service agreements.” Most agreements offered by ACCA contractors cover an inspection of the entire HVAC system and routine maintenance (such as replacing or cleaning filters).
Energy Consumption
The HVAC system is most likely the single biggest use of energy in a building. In commercial applications where refrigeration is applied (combined with the HVAC systems), huge amounts of energy are used in the building. In fact, over a third of the energy used in the United States is used to heat and cool buildings.
According to the Consortium for Energy Efficiency (CEE), up to 50% more energy can be saved with proper installation, sizing, and maintenance of commercial central air conditioning and heat pumps.
Out of Sight, NOT Out of Mind
The cliché “out of sight, out of mind” is often the reason for neglected maintenance on HVAC systems. HVAC systems are usually installed where they aren’t seen, such as in a section of the basement, on rooftops, or in mechanical rooms, making them easy to ignore. The systems are simply taken for granted, until they fail. Decreased efficiency, utility overpayment, discomfort, loss of productivity, premature replacement, and higher repair costs are the result.
Getting your HVAC system checked a least twice annually is just as important as changing the oil in your car every 3,000 miles!
What should you expect your ACCA member service technician to do during a PMA visit?
- Check system functions, safety controls,
and adjust the operating sequence where appropriate.
- Inspect electrical components
and connections and repair/replace or tighten as required.
- Ensure proper airflow
and change dirty air filters.
- Inspect pumps, lubricate and check flow rates where
appropriate.
- Clean and lubricate motors as required.
- Examine belts, adjust and align as required.
- Inspect, clean and balance blowers as required.
Spring Visit (preparation for summer season)
- Clean inside coil, condensate pans, condensate traps, and condensate lines to prevent obstructions.
- Clean outside coil and straighten fins for efficient operation.
- Check refrigerant levels and if low, find the leak and fix it. (According to many equipment manufacturers, a 10% refrigerant loss will result in a 20% decrease in system efficiency!)
- Clean the burner assembly.
- Remove soot from fireside of burner.
- Clean and check operation of humidifier.
- Inspect the heat exchanger for cracks.
- Adjust air-to-fuel ratio of burner and perform combustion analysis.
What’s your bottom line?
Savings: PMAs typically more than pay for themselves through higher efficiency, lower utility bills, and contractor discounts. PMA customers typically receive a discount on all parts and services performed during the entire year.
Peace of Mind: Predictive maintenance will mean fewer system failures and a longer life for your HVAC equipment.
Priority Service: Should a system failure occur during the heat of the summer or the cold of the winter, customers with PMAs generally receive priority service.
Continuity: Many ACCA contractors assign technicians to specific customers. That way, you get to see and know the same service technician, and he or she becomes more familiar with you and your equipment.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
The Truth About Mold
There's Good Mold and There's Bad Mold
Molds are the “bleu” in bleu cheese and Roquefort. Molds improve our wine. They produce penicillin and antibiotics and are used widely in the food and beverage industry. Without mold and mold’s decaying mechanism, the natural environment would be overwhelmed with large amounts of dead organic matter.
Despite many harmless and beneficial molds, some molds can be toxic and pose health threats to humans. The Environmental Protection Agency (EPA) cautions that all molds can cause health problems under the right conditions. The word “toxic” refers to mold that produces hazardous compounds, or mycotoxins.
Often included in the list of toxic molds is Stachybotrys Chartarum, a greenish-black mold, which can grow on high-cellulose, low-nitrogen materials such as fiberboard, drywall, paper, dust, and lint – all of which are found in buildings – when these materials become wet.
There is evidence that mold exposure can cause the following symptoms:
- Allergic
reactions, including irritation of the eyes, nose, or throat.
- Flu-like symptoms,
including fatigue, dizziness, headaches, and diarrhea.
- Worsening of asthma.
Mold is a natural byproduct of the fungi family that thrives when organic substances and water combine under certain circumstances. Mold reproduces via spores that can remain dormant, yet viable, for years. They “come alive” again in the presence of moisture.
HVACR mechanical systems are not generators of mold; their metallic surfaces do not provide the organic matter mold needs to grow. However, systems that are not well maintained could support mold growth. It's important that your system:
- Is
designed and installed correctly.
- Is properly and regularly maintained.
- Controls the moisture in your building.
- Uses good filtration methods to keep your air clean.
- Consider augmenting your air conditioner with a dehumidifier. These systems pull the moisture from the building, thus minimizing growth.
- Don’t turn your air conditioner off for long periods of time during the summer. In humid climates, especially, moisture levels can become quite high in buildings, which can permit mold to gain a foothold.
- Install insulation and vapor barriers to prevent condensation on cold objects such as water pipes, beams, and plumbing fixtures.
- Keep sinks, showers, tubs and other wet areas free of standing water.
- Demand architectural, design, and construction methods that prevent water from entering your building in the first place. Areas of concern include improperly pitched roofs, poorly designed balconies, windows, doors, improperly installed flashing, inadequate vapor barriers, and thin stucco.
- Inspect the building exterior at least once a year and repair caulking, roof flashing, and all breaches in the building envelope.
- Purchase a preventive maintenance agreement (PMA) from your ACCA member contractor. A technician will thoroughly inspect the HVAC system, including duct work and filters, twice a year and make any repairs or adjustments necessary. A PMA will save you money in the long run by reducing major repairs, extending the life of the equipment, helping to inhibit mold growth, and ensuring that the system is working at optimum efficiency. If you notice any water pooling or dust in between semi-annual PMA visits, call your professional ACCA member contractor at once.
- Inform your HVAC contractor of your mold concerns and point out locations of suspicion or evidence of mold.
- Educate your family or building occupants about mold, its dangers, and prevention.
The first step is to alert your HVAC contractor and the builder (if the building is relatively new) regarding your concerns. The contractor or builder will inspect for mold. If there is mold, the next step is to identify its type and establish whether it’s toxic. If so, evacuation, abatement, and remediation may be necessary.
The identification of mold requires specialized testing and laboratory analysis. Partly because of media attention to mold issues, mold abatement has become a growth industry, often attracting less than reputable people who may cause more harm than good by not identifying toxic mold, improperly removing it, or charging you for work you don’t need. Check with your state environmental protection or public health agency to find out if mold remediation contractors are required to be certified and licensed.
ACCA member contractors are concerned about the quality of the air you breathe, too, and many have added indoor air quality services to their offerings. If your HVAC contractor does not perform mold analysis, abatement, and remediation, he or she may be able to refer you to a reputable company that is a trained and certified in this kind of work.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
The Air You Breathe
What's in your air and what can you do about it
Unfortunately, in today’s world, pollution is everywhere. And with the type of cleaning products, manmade goods, and activities undertaken within homes and buildings, indoor environments can become very uncomfortable. Even “fresh,” outdoor air has as many as 30 million dust or pollutant particles per cubic foot.
There are, however, measures you can take to lessen the effects of these particles in your building. Since the building is essentially an enclosed system, heating, ventilation, air conditioning, and refrigeration (HVACR) contractors are able to tackle pollution head-on by moving the air through a high-efficiency air cleaner.
What does an air cleaner do?
At its most basic level, an air cleaner filters out the particles that cause irritation, such as pollen, spores, dust, and other contaminates. In order for any air cleaner to work correctly, the particles need to pass through it. Hence, if the particles are not in the air stream (for example, they’re dust on furniture), an air cleaner won’t remove them. However, a good air cleaner will:
- Remove allergy-causing
particles that pass through it.
- Perform well consistently.
- Be economical to maintain.
- Handle a large volume of air efficiently.
A good air cleaner reduces or removes the irritants that cause allergic symptoms. You may choose a portable air cleaner for smaller spaces or a whole-house air cleaner that works in conjunction with your forced-air system to provide cleaner air throughout your building.
What kinds of residential air cleaners are out there?
There are basically two: furnace-mounted, whole-house units and portable single-room units. Both types of cleaners have different models with varying methods of cleaning the air and capacities for doing so. Your dwelling may help determine the right unit for your needs. A room air cleaner may be best in an apartment, for example, while a whole-house unit might work better with a furnace and air conditioning system. It’s important to note that both room and system air cleaners come in a variety of models, and that not all models use the same technology to clean the air.
Each kind of air cleaner has its pros and cons, which may differ depending on your air-cleaning requirements. Take a look at what your needs are based on your dwelling and allergies and talk to your professional HVACR contractor about the best kind for you.
What are the most effective air cleaners?
Media Air Cleaners
These units use high-efficiency pleated filters, or “media,” to remove about 99% of larger particles, including many allergens. With irritants in the spore and pollen range, they are as effective as HEPA filters but not as effective in filtering out the super-small particulates such as bacteria, viruses, and respirable dust. Media air cleaners are cost effective compared to HEPA filters because the filters are usually less expensive and generally need to be replaced only every one or two years.
HEPA Air Cleaners
HEPA (High Efficiency Particulate Air) cleaners also use high efficiency pleated media to remove particles. To be designated HEPA, an air cleaner must remove 99.97% of all particles 0.3 microns in size (such as dust and mold spores). Due to high cost, operational complications, and other problems, HEPA units are usually seen in residential applications as one-room, portable units. When media in these units need to be replaced, it’s often relatively expensive to do so. Some require charcoal filters that need to be cleaned frequently. Warranties for HEPA cleaners are normally one to three years.
Electronic Air Cleaners
There are two types of electronic air cleaners. Both electrically charge particles and attract them to a collection material. The standard electronic air cleaner will collect charged particles on a specially designed “plate.” Most electronic cleaners can obtain 95% efficiency or higher on various particles when the collection plates and ionizing wires are clean, but they can lose some efficiency as they collect dirt.
A newer technology in electronic air cleaners is called “electronically enhanced media” combining elements of both electronic and media air cleaners. Particles are electrically charged and then collected by the massive air cleaning media of a traditional high-efficiency cleaner. Because the replacement of the media is simple and there are no plates to clean, efficiency is maintained throughout the media’s life. Electronically enhanced media air cleaners are 99% effective in the removal of numerous particle categories. Electronic air cleaners generally have warranties of one to five years.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
Comfort By Design
by Jim Herritage, CEM
Before you replace your heating, ventilation, and air conditioning (HVAC) system, there are some things you should know. The first is that a quality installation begins with a professional design.
Most of us don’t think about “design” when we think of heating and cooling, but it’s just as important as a solid architectural design. A professional HVAC contractor won’t simply replace what you have now with new equipment. It’s possible that your existing system wasn’t sized properly to begin with!
To make sure your new HVAC system meets your needs for comfort and energy efficiency, a quality contractor performs a series of calculations that take into account the overall climate where you live; how your building is sited (for example, if it faces south or north); the amount and quality of insulation in walls, basement or crawl space, and attic; how many windows the building has and how efficient they are; other sources of ambient heat, such as kitchen appliances and lights; even landscaping near the house. These are called “load calculations.” The formulas, which are included in ACCA’s Manual J®, were developed by HVAC experts at ACCA and are the industry standard, often incorporated into local building codes.
Turn to the pros
Why should you care about load calculations? It’s simple: an under-sized system can reduce the comfort of your building, use more energy, and not last as long as a properly sized system. An over-sized system will cost more than you need to spend and may contribute to moisture-related problems down the line.
Any contractor who tells you a load calculation isn’t important is not a professional. The professional understands that your year-round comfort is the ultimate goal. In the summer, your air conditioning system not only cools your building’s air (sensible cooling), it removes moisture (latent cooling). In the winter, your heating system must keep you comfortable without causing high utility bills.
The right equipment
The load calculation also enables the contractor to select the right kind of system. Heating and air conditioning equipment comes in many capacities, configurations, and efficiencies. It’s important that your contractor selects the equipment that will be compatible with your building’s heating and cooling needs.
Ducts, grilles, and registers
A qualified contractor will make sure the duct work in your building is the right size and insulated properly. Properly installed and maintained duct work can last twenty years or more, but time, heat, and humidity can degrade the ducts’ insulation. In addition, ducts may have collected contaminates over the years and need to be cleaned out.
Tell your contractor if some of the offices in your building have been too hot or too cold, as this could be a sign that the ducts are the wrong size or are dirty. The contractor will evaluate the amount of air each office should get and verify that your duct system is clean and configured to deliver the right air to the right office.
Your return air grilles and supply air registers play an important role in providing heating and air conditioning comfort, too. There are times when simply replacing one or more of these devices can cause a noticeable improvement in your building’s thermal comfort.
Return grilles that are undersized can reduce the efficiency of the air conditioning system as well as the comfort in your building. Your contractor will verify that these devices are sized and operating properly and may make suggestions for improved performance.
Select a professional
Buying a new comfort system is a major expense, and most building owners replace their heating and air conditioning systems only every ten or twenty years. It just makes sense – and cents! – to choose a contractor who knows how to design, install, and service the right equipment for you. Using a professional contractor assures you that your building will be comfortable for many years to come.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
Efficiency & Comfort
Tips for Maximum Efficiency and Comfort
Are you getting the most for your comfort dollar? Or are you paying to heat and cool the neighborhood?
Whether your comfort system is old or new, in a new or old building, a multi zoned or a single zoned building, there are many little things you can do to optimize its efficiency and minimize your utility bills. They’re definitely worth the small amount of time and expense they take, because in the long run, they’ll save you money.
Outside
Whatever the season, you want to keep your comfortable air inside the building. That means caulking and weather stripping doors and windows, around chimneys and flues, and anywhere else inside air can escape.
Inspect the exterior of your building once or twice a year. A good way to remember is to do it when you have your regular, professional HVAC check-up because heating and cooling will be on your mind anyway.
Keep vegetation and debris well away from the outdoor unit of your system. They can block air flow, which forces the system to work harder to produce the same level of comfort. You’ll spend more now … and in a few years, when the equipment fails prematurely and you have to replace it.
Inside
Set the thermostat at the highest comfortable level in the summer and the lowest comfortable level in the winter. A change in one degree changes energy consumption by about 4%. Humidifiers and dehumidifiers can make a huge difference in how the temperature feels.
Install a programmable thermostat. It will automatically adjust the temperature at night or when you’re not going to be building for a long period of time.
Lights are a source of indoor heat, a problem in the summer. Wherever possible, replace incandescent bulbs and fixtures with compact fluorescents. They use a lot less energy, produce less heat, and last longer. Today’s fluorescents aren’t like those of only a few years ago – you can choose a warm, yellow light similar to incandescent light. You can use them in table lamps, ceiling fixtures (including ceiling fan fixtures), torchieres, and for indoor and outdoor lighting. Some can be used with dimmer switches, too. Avoid halogen lamps. The light is clear and bright, but they create a lot of heat.
In the summer, keep blinds closed on the sunny side of the house during the day. In the winter, open them to take advantage of solar heat but close them at night to help block cold air (even if you have insulated windows).
Insulate attics, crawl spaces, basements, and walls to the R value recommended for building area. Your HVAC contractor can tell you how much you need. Don’t forget to insulate duct work in un-conditioned space.
HVAC System
Check filters regularly and clean or replace them when needed. Your HVAC technician will tell you how often that’s likely to be based on the manufacturer’s recommendations and local air quality conditions.
Make sure room vents are working properly. Close them at least part-way in rooms you’re not using. Never block them with furniture, pictures, or window coverings.
Consider a zoned system if your building two or more stories or areas. A programmable thermostat in each zone can save energy and money.
© Air Conditioning Contractors of America Association, Inc., www.acca.org.Reprinted with permission.
Humidity
It’s All Relative
Proper humidity levels keep you healthier and more comfortable.
Your heating, ventilation, and air conditioning (HVAC) system can do more than heat and cool your building. It can also keep the humidity at a comfortable level in winter and summer. It’s a delicate balance: if it’s too low, you’ll feel the effects of colds, respiratory infections, and asthma more, and some of the furnishings in your building will literally dry out. If it’s too high, you’ll be uncomfortable but mold and mildew will flourish. They love moisture!
HVAC systems balance temperature and humidity. The best person to design a system appropriate for your climate and your comfort needs is a professional ACCA member contractor. He or she understands the science of your building and applies the principles contained in the ACCA design and technical manuals to the design, selection, and installation of an HVAC system that’s right for you.
ACCA manuals are the industry standard, often incorporated into local building codes and endorsed or recommended by the Department of Energy, the Environmental Protection Agency, and equipment manufacturers.
Relatively Speaking …
Relative humidity (RH) is the percent of moisture actually in the air compared to the maximum amount of moisture the air can hold at that temperature. Cold air can hold less moisture than warm air. At 70ºF, air can hold as much as 12 times the amount of moisture as 10ºF air. That’s why it’s usually more humid in the hot summer months.
Winter Humidification
Most heating systems just heat the air, changing the temperature, not the humidity. Cold air is dry, and forced-air systems and heat pumps pull outside air for heating. When 10°F outside air is heated to 70°F, the humidity level in your building will be the same as the outside air’s, around 7%. That’s one reason your skin feels dryer, perhaps even chapped, in the winter. So in dry cold climates, you will probably want to add a humidifier to your heating system.
The effects of bacteria, viruses, fungi, respiratory infections, allergic rhinitis and asthma, and ozone production during the winter can be minimized by higher humidity levels. Studies have shown that wintertime levels of 68°F/60% RH are just as comfortable as 72°F/30% RH; so by increasing the RH and lowering the temperature, you will minimize negative effects while lowering your utility bills.
Because the outside air temperature and RH can change in a short time, even a few hours, a computer-controlled humidifier is probably your best choice. It will automatically adjust for these fluctuations to provide enough moisture for a healthy, comfortable building and minimize or prevent window and cold surface condensation.
Summer Dehumidification
Air conditioners pull moisture from the air (HVAC professionals call that “latent heat,” as opposed to “sensible heat,” the temperature) as they cool it, which is one reason you feel better in an air conditioned building. If they didn’t, you’d feel cold and clammy instead of cool and comfortable. In particularly hot and humid climates, however, you may need to augment the dehumidifying capacity of your system.
Very high moisture levels give you that “sticky” feeling and may lead to health problems resulting from the growth of bacteria, viruses, fungi, dust mites, and mold. Air at 78°F/30% RH provides the same level of comfort as does 74°F/70% RH air. In the summer, turning the thermostat up lowers your utility bills, so dehumidifying can save you money as well as add to your comfort.
Although your air conditioning system or stand-alone dehumidifier is designed to remove moisture and decrease the RH levels in your building, in very humid areas of the country, it may not be capable of lowering the levels below 60% RH. In such cases, your ACCA quality contractor may suggest alternative or additional equipment and control strategies.
It’s Your Choice!
The choice is yours: a comfort and health indoor air system, or a furnace/boiler and an air conditioner. Since more than a third of your time is spent in your building, it is important to make the right choice.
© Air Conditioning Contractors of America Association, Inc., www.acca.org. Reprinted with permission.