What? You don’t want to buy 10 portable humidifiers and constantly refill the units with water? That’s crazy!

Monday, October 28, 2013 by Aprilaire Team

What? You don’t want to buy 10 portable humidifiers and constantly refill the units with water? That’s crazy! Check out this article from AirRite Air Conditioning about the top six reasons to get a whole-house humidifier. http://blog.airrite.com/2012/10/16/whole-house-humidifier/

How many of you understand what relative humidity is? Come on, be honest!

Sunday, October 27, 2013 by Aprilaire Team

How many of you understand what relative humidity is? Come on, be honest! Here’s a nice article from How Stuff Works explaining relative humidity in layman’s terms: http://science.howstuffworks.com/dictionary/meteorological-terms/question651.htm

Do you take pride in keeping your home in great condition?

Saturday, October 26, 2013 by Aprilaire Team

Do you take pride in keeping your home in great condition? Who would ever think controlling your indoor humidity can help you preserve your wood floor, electronics and wallpaper? Here’s how: http://www.aprilaire.com/index.php?znfAction=IAQProblems&category=protection

Are you losing sleep because of sticky, humid nights?

Friday, August 9, 2013 by Aprilaire Team

Are you losing sleep because of sticky, humid nights? This is because of too much humidity in your home! Aprilaire whole-house dehumidifiers help make homes more comfortable. Learn more here: http://www.aprilaire.com/index.php?znfAction=ProductDetails&category=17&item=1700

 

Perform Aprilaire Humidifier Annual maintenance like a boss!

Monday, April 22, 2013 by Aprilaire Team

For best performance, we recommend you replace the Water
Panel evaporator in your Aprilaire humidifier at least annually with
the exception of Models 400 and 400M, which should be changed at
least twice per heating season.

The “Change Water Panel” indicator light (Digital Control only) will blink
when it is time to change your Water Panel. See individual model instructions
for additional maintenance.

To purchase a new Water Panel:

• Visit estore.aprilaire.com

• Call the installer of your Aprilaire humidifier.

• Call your heating and air conditioning dealer.

• Use our “Dealer Locator” at: www.aprilaire.com

• Purchase only Genuine Aprilaire Water Panels to maintain best performance.

If your humidifier is equipped with a Digital Humidifier Control with Water
Panel change indicator, after replacing the Water Panel, turn the control
knob to the “Test/Reset” position until the “Humidifier On” light blinks to
reset its timer. (Blower must be operating and HVAC calling for heat.) Be sure
to turn the control knob back to it’s original setting. If the “Humidifier On”
light continues to blink, your humidifier is in Test mode. DO NOT LEAVE THE
CONTROL IN TEST MODE OR HUMIDIFIER WILL NOT OPERATE.

Also review the periodic preventavtive maintenance in the owner's manual.

Blower Motor Cycling Issue

Monday, February 18, 2013 by Customers Sharing Stories

Consumer feedback:

I have the Model 700 with the Model 58 humidistat. The problem I'm having is that the humidistat is callingtne furnace to start the blower motor I guess because the humidity has fallen below what it needs to be. However, the blower motor comes on for like 10 seconds and the shuts off. It will repeat this cycle 100 times a day so I have to turn the humidistat off. It generally only does this during the day because the thermostat is set to a temp that generally doesn't require heat. The HVAC guy has replaced the humidistat already with no success. My furnace is an Amana prane model. What's going on with this? Thanks

Name: Ken
City: Middletown
State: MD

 

Aprilaires' reponse:

Dear Ken,

Thank you for contacting us with regards to your model 700 Humidifier. Based on the information provided, it’s not clear how this humidistat has been wired. Normally, the model 58 humidistat does not have the ability to operate your furnace fan without an additional relay. It’s possible that this relay has not been wired properly. We would recommend that you have your HVAC guy contact us when he’s next on-site. We can provide troubleshooting assistance by phone.

We look forward to assisting you with this issue.

1-800-334-6011 Ext.6172
Call Center hours are M-F, 7 a.m. to 5 p.m. CST
Visit www.aprilaire.com

Stop the spread of the flu with proper humidity control?

Friday, January 25, 2013 by Aprilaire Team

ROCHESTER, Minn. — A Mayo Clinic researcher is testing the theory that controlling indoor humidity levels can help control the influenza virus in transmission hotspots like schools, hospitals, daycare centers and churches.

The virus can spread quickly in those areas, especially in the winter time when low humidity levels help the influenza virus survive longer outside the human body.

Read more...

Save money with proper humidity control in YOUR home!

Monday, October 22, 2012 by Aprilaire Team

We are always looking for ways to save a little money without compromising our comfort, review these money saving tips from We Energies… Take special notice to the proper humidity control, it goes both with adding and removing it from our homes.

Keep your Humidifier Running at Peak Performance by following these Annual Maintenance Tips

Thursday, October 18, 2012 by Aprilaire Team

For best performance, we recommend that you replace the Water
Panel evaporator in your Aprilaire humidifier at least annually with
the exception of Models 400 and 400M which should be changed at
least twice per heating season.

The “Change Water Panel” indicator light (Digital Control only) will blink
when it is time to change yourWater Panel. See individual model instructions
for additional maintenance.

To purchase a new Water Panel:

• Visit estore.aprilaire.com
• Call the installer of your Aprilaire humidifier.
This information is often found on your equipment.
• Call your heating and air conditioning dealer.
• Use our “Dealer Locator” at: www.aprilaire.com
• Purchase only Genuine Aprilaire Water Panels to maintain performance.

If your humidifier is equipped with a Digital Humidifier Control with Water
Panel change indicator, after replacing the Water Panel, turn the control
knob to the “Test/Reset” position until the “Humidifier On” light blinks to
reset its timer. (Blower must be operating and HVAC calling for heat.) Be sure
to turn the control knob back to it’s original setting. If the “Humidifier On”
light continues to blink, your humidifier is in Test mode. DO NOT LEAVE THE
CONTROL IN TEST MODE OR HUMIDIFIER WILL NOT OPERATE.

Also review the periodic preventavtive maintenance in the owners manual.

Harmful Effects of Mold

Thursday, October 18, 2012 by Aprilaire Team

Harmful effects of molds

The type and severity of health effects that result from molds exposure is widely variable among different locations, from person to person and over time.

Although difficult to predict, exposure to molds growing indoors is most often associated with the following allergy symptoms:

  • Nasal and sinus congestion
  • Cough/sore throat
  • Chest tightness
  • Dyspnea (breathing difficulty)
  • Asthma (or exacerbation of it)
  • Epistaxis (nosebleed)
  • Upper respiratory tract infections
  • Headache
  • Skin and eye irritation

 

Indoor molds exposure leads mostly to upper respiratory tract symptoms

Long-term exposure to indoor molds is certainly unhealthy to anyone, but some groups will develop more severe symptoms sooner than others, including:

  • Infants and children
  • Elderly people
  • Individuals with respiratory conditions, allergies and/or asthma
  • Immunocompromised patients

Some indoor molds are capable of producing extremely potent toxins (mycotoxins) that are lipid-soluble and readily absorbed by the intestinal lining, airways, and skin. These agents, usually contained in the fungal spores, have toxic effects ranging from short-term irritation to immunosuppression and cancer. (Photo: Mold growing behind wallpaper)

More severe symptoms that could result from continuous human exposure to indoor mycotoxigenic molds include:

  • Cancer (aflatoxin best characterized as potential human carcinogen)
  • Hypersensitivity pneumonitis/pulmonary fibrosis
  • Pulmonary injury/hemosiderosis (bleeding)
  • Neurotoxicity
  • Hematologic and immunologic disorders
  • Hepatic, endocrine and/or renal toxicities
  • Pregnancy, gastrointestinal and/or cardiac conditions

It is important to notice that the clinical relevance of mycotoxins under realistic airborne exposure levels is not fully established. Further, some or much of the supporting evidence for these other health effects is based on case studies rather than controlled studies, studies that have not yet been reproduced or involve symptoms that are subjective.
(Photo: Black mold spores micrography)

Among the indoor mycotoxin-producing species of molds are Fusarium, Trichoderma, and one that, although less commonly isolated, became notorious during the past decade, Stachybotrys atra (aka S. chartarum, black mold). Between 1993 and 1994, there was an unusual outbreak of pulmonary hemorrhage in infants in Cleveland, Ohio, where one kid died. Researchers found that the kids’ homes had previously sustained water damage that resulted in molds contamination, and the quantity of molds, including S. chartarum, was higher in the homes of infants with pulmonary hemorrhage than in those of controls. (Photo: Stachybotrys growing on Potato Dextrose Agar (PDA))

It was this Cleveland event that initiated the headline news of Stachybotrys. The American Academy of Pediatrics produced guidelines in the wake of the outbreak. Other incidents involving kids in Stachybotrys-contaminated water-damaged school buildings have captured headlines as well, with children becoming symptom-free after being removed from those environments.
Article from the Fargo Forum newspaper, North Dakota (5/1/1997)

The role of S. chartarum in pulmonary hemorrhage in the Cleveland incident and in human health in the indoor environment is not clear though. There is not enough evidence to prove a solid causal relationship between S. chartarum and these health problems. Actually, in 2000 the CDC released two reports critical of the study conducted in Cleveland and concluded that the association between S. chartarum and acute pulmonary hemorrhage was not proven.

While case studies certainly indicate the possibility or even the plausibility of an effect from molds exposure, such studies by their nature cannot address whether the effect is common or widespread among building occupants. Results from studies that have not been reproduced may be spurious or have yet to be confirmed by well-designed follow up studies. (Photo: Moldy humid walls in a closet space)

In large epidemiologic studies, general symptoms have been associated with moisture damaged and presumably moldy buildings. Many of the reported symptoms are subjective and difficult to quantify. Results are confounded by the fact that the association is general, and mold is not the only possible cause of the symptoms. Neither condition proves that mold is NOT a cause.

In any case, molds growth in the indoor environment should be considered unacceptable from the perspectives of potential adverse health effects and building performance.

Dose-response

There is almost a complete lack of information on specific human responses to well-defined exposures to molds contaminants. There is currently no proven method to measure the type or amount of mold that a person is exposed to, and common symptoms associated with molds exposure are non-specific, aggravated by the facts that molds are present everywhere in the environment and that responses to exposure vary greatly among individuals. (Photo: Heavy mold growth on the underside of spruce floorboards)

There are no accepted standards for molds sampling in indoor environments or for analyzing and interpreting the data in terms of human health. Most studies are then based primarily on baseline environmental data rather than on human dose-response data. Neither OSHA or NIOSH, nor the EPA has set a standard or PEL for molds exposure.

Mold growth on air diffuser in ceiling
Miller et al. (1988) stated that it is reasonable to assume there is a problem if a single species predominates with >50 CFU/m3, that <150 CFU/m3 is acceptable if there is a mix of benign species, and that there is no problem when up to 300 CFU/m3 of Cladosporium or other common fungi is isolated. There is no source material to support these assertions, as few inhalation studies have been conducted.

References

American Academy of Pediatrics Committee on Environmental Health. 1998. Toxic effects of indoor molds. Pediatrics. 101:712-714. 11/23/03

Centers for Disease Control and Prevention. 2002. State of the Science on Molds and Human Health. 11/15/03

US Environmental Protection Agency – Indoor Air Quality – Molds. 11/15/03

Kuhn, D. M., and M. A. Ghannoum. 2003. Indoor mold, toxigenic fungi, and Stachybotrys chartarum: infectious disease perspective. Clin Microbiol Rev. 16(1):144-172. 11/15/03

Miller, J. D., A. M. Laflamme, Y. Sobol, P. Lafontaine and R. Greenhalgh. 1988. Fungi and fungal products in some Canadian houses. Int. Biodeterior. 24:103-120.

Morbidity and Mortality Weekly Report – Centers for Disease Control and Prevention. 2000. Update: Pulmonary Hemorrhage/Hemosiderosis Among Infants --- Cleveland, Ohio, 1993-1996. 49(9):180-184. 11/17/03

Nelson, B. D. 2001. Stachybotrys chartarum: The Toxic Indoor Mold – APSnet. 11/23/03

What Types Of Mold Are Considered Toxic Mold

"Toxic mold" is a term that is used to describe types of mold that are considered deadly to humans. Most people believe that the name refers to one particular species of mold; however, it encompasses hundreds of species, a small fraction of which are not very harmful to the human body. Black mold is commonly used as a name for the most harmful mold species, which happen to be black in appearance. However, even molds of a different color can be toxic to the human body.

Any place that is dark and where there is an accumulation of moisture, is a potential breeding pool for mold. Mold can grown on almost any organic surface as long as moisture and oxygen are present. When large amounts of moisture build-up in buildings, or building materials mold growth will occur. It is virtually impossible to remove all indoor mold and mold spores, but it is possible to manage.

People are exposed to some amount of mold everyday. When mold is growing on a surface, spores can be released into the air where a person can then inhale them. A person who is subject to inhaling a large amount of these spores may be subject to some medical damage.

There are five categories of toxic mold. They are Cladosporium, Penicilium, Fusarium, Aspergillus, and Stachybotrys. Some of the species included in these categories may only cause hay fever-like allergic reactions, while others can cause potentially deadly illnesses. All five of these mold families can be found lurking indoors, in damp spaces. Each has its own particular characteristics that can greatly affect whatever organism or material it contacts. Indoor mold is not always obvious. Mold can manifest on hidden surfaces, such as wallpaper, paneling, the top of ceiling tiles, and underneath carpet.

Stachbotrys

The toxin produced by Stachybotrys chartarum is the most deadly. It has been tied to diseases as minor as hay fever, to those as serious as liver damage, pulmonary edema, and in the most severe cases, brain or nerve damage and even death. It has also been linked to severe illness in infants. Those with compromised immune systems, small children, and the elderly are highly susceptible to illness when they come in contact with this species of mold. Some symptoms associated with exposure to Stachbotrys include:
respiratory issues
nasal and sinus congestion
eye irritation
sore throat
hacking cough
chronic fatigue
central nervous system issues
aches and pains

Cladosporium, Fusarium, and Penicillium

These mold families have been connected to illnesses such as nail fungus, asthma, and also infections of the lungs, liver, and kidneys. Additionally, Fusarium may cause gastrointestinal illnesses, and even illness which affect the female reproductive system. Chronic cases of Cladosporium may produce pulmonary edema and emphysema.

Aspergillus

The least serious of the toxic mold groups, the Aspergillus mold family consists of over 160 species. Only 16 of those cause illness in humans, none of which are fatal if treated.

Toxic molds produce chemicals during their natural growth that are classified as toxins or poisons. The types that have been found to have profound effects on human health, are given the label of "toxic mold."

Toxic molds are all very dangerous if allowed to grow inside the home. Proper precautions should be taken to prevent and eliminate their growth. These measures should include eliminating every material that nourishes the molds, such as old remodeling materials left in a basement. Also, never try to determine the type of mold in your home. Contact a professional to test any mold colony you may find, and consult with your family physician.

Scary Facts About Termites!

Thursday, October 18, 2012 by Aprilaire Team

Can you imagine resting your arm on your wall talking to a friend at a house party just to watch bedroom wall cave in. This interesting information was posted by ABC news the other day and I thought I re-share. I have had one case of this in Northeast Ohio that was a nightmare and a lesson for the owner. Forget about killer bees and voracious fire ants. Aggressive termites that can destroy a new house almost before the paint dries and may be heading for a home near you.

Formosan termites cause about $300 million in damage in New Orleans each year, and now they are moving north, east and west. They've already been found in at least 11 states, and scientists say they can attack with such vengeance that they make domestic termites seem almost tame.

East Asian Immigrants

These fierce little critters arrived in southern ports from East Asia at the end of World War II and lay low for decades, gradually increasing their numbers until they were strong enough to attack with gusto. For years now they have plagued New Orleans, which seems to have been built for their specific needs, and scientists have all but given up hope of ever eliminating them from that area.

They've already eaten through scores of structures in the city's famed French Quarter, and when they are finally flushed from a building they take up residence in living trees. Thousands of trees have been killed by the termites, many of which have fallen on structures, causing even more damage.

Ed Bordes, director of the New Orleans Mosquito and Termite Control Board, estimates that 30 percent of the city's live oaks and cypress trees are now infested.

Until fairly recently, scientists had thought the termites were pretty well isolated in the Deep South, but that clearly has changed. Damage estimates across several states now range between $1 billion and $2 billion per year, about the same as caused by all the domestic species combined.

Power in Numbers

Formosan termites have established strongholds from Florida to California, and although scientists first thought the termites would restrict their habitat to warm areas, that may not be the case. Those damp basements in northern regions may be very much to their liking.

According to the Agricultural Research Service of the U.S. Department of Agriculture, which is heading up a New Orleans-based Formosan termite project called Operation Full Stop, these hungry little devils are the most voracious termites in the world. Here are a few reasons why:

Their colonies are huge, thus enabling them to do great damage in a very short period of time while fighting off nearly all efforts to bring them under control. A colony of domestic termites usually ranges in the thousands; Formosan colonies number in the millions.

Domestic colonies will eat about 7 pounds of wood per year. A Formosan colony will eat about 1,000 pounds per year.

They don't just eat wood. When they get thirsty, Bordes says, they can eat the seals out of high-pressure water lines to get at the moisture inside. And they can penetrate cement, brick, plastic and other materials to get to food and water.

A queen termite can lay 2,000 to 3,000 eggs a day, ensuring the survival of colonies that can last for decades.

Come springtime, New Orleans residents can look forward to something locals describe as nothing short of terrifying. Colonies will send out winged "soldiers" by the millions, forming flying armadas that can almost turn the sky dark as they seek out new areas for harvesting.

They're not particularly discriminating. They like new houses as well as old. And it doesn't take them long to do a lot of damage.

Eradication Impossible

By the time they were discovered in one 2-year-old house, they had already eaten out one wall from the basement to the roof, according to scientists who are working desperately to come up with a means of controlling the termites. That doesn't mean eliminating them, at least not for New Orleans.

"Eradication is not a likely scenario," according to one report from the Agricultural Research Service.

But at least the scientists know where to start. New Orleans has become a working laboratory, with residents setting out traps to capture enough of the little beasts for scientists to study. Formosan termites are there in great numbers because they couldn't have designed it better themselves, at least from a termite's perspective.

The city has just the right climate, humid and hot. And many of those wonderful old buildings that dot the city's historical areas are sitting directly on the ground, giving the subterranean termites easy access. Many of the buildings share common walls, allowing the termites to move right on down the street without even venturing outside.

They also build underground tunnels extending hundreds of feet in various directions, thus expanding their options.

According to researchers, sometimes nobody knows there's a problem until a wall falls down.

Fighting Back

The best defense appears to be an offense, according to the scientists. Once the termites establish themselves with huge colonies, it's probably too late to do much about it. So the goal is to nip it early, identifying the termites as they move outward and wiping out colonies before they get too large.

Unfortunately, the critters are pretty clever. Other termites are routinely treated by injecting poison into the ground, but Formosan termites can just move their nests above ground, thus avoiding the toxins.

And not a lot of toxins are effective. The most potent treatment, chlordane, was outlawed in 1988 because it remains active in the soil for 25 years, thus threatening human health as well as other animals. Scientists are now experimenting with growth regulators that will keep the termites from maturing, and they are looking for biological ways to inhibit procreation and even communication within the colony.

They've made some progress, but for now the Formosan termite still has the upper hand. It will take a persistent, expensive, grass-roots effort across many states to bring the problem under control.

 

Stanley Stepak Jr. M.A.

Mechanical Ventilation

Thursday, October 18, 2012 by Aprilaire Team

The Need for Mechanical Ventilation

History of Ventilation in Houses
Houses need to have an indoor/outdoor exchange of air to replenish oxygen used by the occupants and to remove pollutants generated by breathing, household activities and emissions from building materials and furnishings. For many years, houses were constructed without mechanical ventilation systems and relied on air leakage through the building envelope to provide this indoor/ outdoor air exchange during the winter months.

In the past, this natural form of ventilation worked fairly well. Houses built before the 1960s tended to be quite leaky and pressure differences between the inside and outside, caused by wind or temperature difference, were sufficient to provide a significant amount of air exchange most of the time. However, a leaky building envelope does not always guarantee adequate air exchange. The movement of air requires both a pathway (e.g., a leak) and a pressure difference, and even a leaky house will experience periods when there is no indoor/outdoor air exchange. These periods are most likely to occur during the spring or fall, when winds are light and there is little or no indoor/outdoor temperature difference that can create a stack effect. The leakier the house, however, the less frequent the periods of inadequate air exchange.

Since most fuel-fired systems consume air from the house, and this air must then be replaced by leakage from outdoors, the operation of fuel-fired systems promotes some indoor/outdoor air exchange. The chimneys associated with these systems also provide a major leakage point, thus promoting air exchange even when the heating system is not operating. As well, a chimney tends to raise the level of the neutral pressure plane, thus reducing the outward pressure difference across the building envelope and, with it, the potential for interstitial condensation (i.e., condensation that occurs within the building envelope) caused by air leaking out of the house.

In houses built prior to the 1960s, the amount of air exchange provided by leakage was generally regarded as sufficient. But in the '60s, a number of factors changed this picture, including the increased use of electric heating in houses. Unlike fuel-fired systems, electric heating systems do not require the replacement of air, nor do they require chimneys. Consequently, electrically heated houses have a greater tendency to experience high humidity levels, interior surface moulds and interstitial condensation.

In the early 1970s, in response to these problems associated with electrically heated houses, Canada Mortgage and Housing Corporation (CMHC) took the step of requiring all NHA-financed electrically heated houses to incorporate exhaust fans, a requirement that was eventually incorporated into the National Building Code. By the mid-70s, these problems had became so apparent that CMHC contemplated not allowing electric heating in houses financed under its National Housing Act mortgage insurance program.

In addition to the increase in the use of electric heating, the 1960s brought the construction of houses that were much more airtight as a result of new products and practices, which included the substitution of panel sheathings, such as plywood and waferboard, for board sheathing; the replacement of paper-backed insulation batts by friction-fit batts and polyethylene film; improved caulking materials; tighter windows and doors; and more efficient heating systems.

When the energy crisis developed in the early 1970s, considerable emphasis was placed on reducing air leakage in order to conserve energy. The use of electric heating systems was encouraged and higher efficiency furnaces were developed further reducing airchange rates in buildings. This trend towards greater airtightness and higher efficiency furnaces gave rise to concerns that the exchange of air in houses by natural means might be insufficient in some instances to provide adequate air quality thus increasing the risk of health problems among the occupants. Condensation problems resulting from higher humidity levels were also a concern.

How Much Indoor/Outdoor Air Exchange Is Necessary?
The air-change needs of houses are not uniform. Not only do they vary from house to house according to the number of occupants, and the presence and strength of various pollutant sources, but, for any given house, they also vary with time as occupants come and go, and pollutant sources wax and wane. Nevertheless, ASHRAE Standard 62, Canadian Standards Association Standard CAN/CSA-F326 and the National Building Code of Canada (NBC) have all established levels of air change that can be expected to meet the peak or near-peak needs of a majority of normal households. (The latter two are based to some extent on ASHRAE Standard 62.)

All three approaches suggest an air change rate of about 0.3 air changes per hour (ach). This is the level of air change used internationally as the norm in terms of analyzing the success of various ventilation schemes. Again, it is recognized that few, if any, houses require constant air change at the rate of 0.3 ach. However, if a house is so tight that leakage fails to provide this level of air change for significant periods of time, it is likely that many such periods of shortfall will coincide with periods when this level of air change is required. When this happens, poor indoor air quality, high humidity, surface moulds and interstitial condensation can result.

How Airtight Are Recently Built Houses?
In 1989, a study to determine the airtightness of recently constructed houses in various regions of Canada was conducted. Airtightness was measured by carrying out fan-depressurization tests on nearly 200 houses throughout the country. The test results were analyzed to estimate the indoor/outdoor air change rate that could be attributed solely to the air leakage likely to be experienced by each house over a typical heating season. The results of the study allowed the researchers to make the following predictions:

  • More than 70% of the surveyed houses would have an average air-leakage rate of less than 0.3 ach over the entire heating season.
  • Almost 90% of the surveyed houses would have at least one month during the heating season when the average air-leakage rate was less than 0.3 ach.
  • Virtually all of the surveyed houses (99%) would have at least one 24-hour period over the heating season in which the average air-leakage rate was less than 0.3 ach.

These results seem to indicate that a majority of houses being built in Canada using normal construction practices are close enough to being airtight that air leakage through the envelope cannot be relied on to provide the rate of air change deemed necessary to maintain adequate indoor air quality in a typical household. While the rate of air change through the building envelope may be adequate most of the time, it may not be all of the time. Therefore, to ensure that a satisfactory rate of air change is attainable at all times throughout the heating season, these houses must be provided with mechanical ventilation systems.

Characteristics of an Ideal Mechanical Ventilation System

Currently available technology is not able to provide an ideal mechanical ventilation system for houses. But before looking at the methods of mechanically ventilating houses that are available today, it is helpful to identify the characteristics of an ideal system:

Operate when needed
The system would operate whenever additional indoor/outdoor air exchange is needed and would do so without the need for occupant intervention.

Operate only when needed
This is important since a mechanical ventilation system has costs associated with it — the cost of the electricity to run it and the cost of heating the outdoor air that the system brings in. (The latter can be reduced by incorporating heat-recovery capabilities in the system, but cannot be eliminated altogether.) Therefore, the system should not operate during those periods when no indoor/ outdoor air exchange is required. The length, timing and frequency of such periods vary from household to household. Air exchange is not required when:

  • there are no occupants in the house
  • there are no activities or processes underway that generate pollutants
  • there is sufficient air exchange due to wind or stack effect to meet the household's needs.

Provide needed amount of air exchange
The system would be able to deliver enough outdoor air to meet the probable maximum needs of the household. It would also be capable of modulating delivery so that it did not deliver more outdoor air than required at times of reduced need. A system that does not have this capability is likely to provide too much outdoor air most of the time it is in operation, resulting in excess energy costs and low humidity. As well, a system that is unresponsive can annoy the occupants, possibly to the point that they simply turn it off altogether.

Distribute outdoor air where needed
It is not enough that the mechanical ventilation system change the air in the house as a whole to meet the standard of 0.3 ach. The system must also be able to deliver the outdoor air to those parts of the house where the occupants are likely to spend most of their time — the living room, the kitchen and the bedrooms.

Be quiet
The system would be quiet enough so that the occupants would not be tempted to turn it off to reduce noise.

Not interfere with other systems
There is significant potential for mechanical ventilation systems to interfere with the operation of other systems, such as certain types of fuel-fired heating systems. Under these circumstances, if the ventilation system creates a high negative pressure in the house, the products of combustion (which can be harmful to the occupants) can spill into the house rather than flowing up the chimney to the outdoors.

Not interfere with the building envelope
The system would not create significant positive pressure in the house since this could drive humid air from the house through the building envelope, resulting in interstitial condensation.

Demand-Controlled Ventilation

The first two characteristics of the ideal mechanical ventilation system described above are related to the issue of control. A system that embodies these characteristics is known as a "demand-controlled ventilation system." Such a system would ideally be controlled by an array of sensors — one for humidity and one for every possible pollutant that the ventilation system would have to respond to, including carbon monoxide, carbon dioxide, formaldehyde, volatile organic compounds, etc. The system would bring in outdoor air and/or extract indoor air until all of these sensors determined that specific pollutants were at, or below, predetermined safe levels. Whenever a sensor detected a pollutant above its safe level, the ventilation system would operate.

A less-than-ideal demand-controlled ventilation system would have at least one sensor. For example, many ventilation systems are controlled by dehumidistats: the system operates until the dehumidistat has determined that the humidity in the house is at a safe level. Excess humidity is one of the main reasons that ventilation is required, but not the only one. The amount of ventilation required to control humidity may not be sufficient to control other pollutants since this depends on the activities of the occupants, on the relative strengths of other pollutants and on the level of humidity.

Carbon dioxide (CO2) sensors are sometimes used to control ventilation systems in large buildings, and this technology is just now becoming available for residential use. Increasing CO2 concentration is usually a good indicator of decreasing air quality but it may not be adequate in cases where there are unusual pollutants, such as those generated by certain hobbies.

The ideal system requires the full array of sensors mentioned above. However, at present this ideal is not attainable because:

- there is insufficient knowledge and information to determine

- which pollutants should be monitored, and

- what the acceptable levels for a particular pollutant

- practical, reliable and economical detectors for all pollutants of concern are not available.

While research and development is underway in many countries to try to address these issues, breakthroughs are not expected in the near future.

For a discussion of current approaches to mechanical ventilation systems for houses, please see Construction Technology Update No. 15.

References

1. ASHRAE 62-1989, Ventilation for Acceptable Indoor Air Quality. American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, GA.

2. Standard CAN/CSA-F326-M91, Residential Mechanical Ventilation Systems. Canadian Standards Association, Etobicoke, ON.

3. National Building Code of Canada, 1995. Canadian Commission on Building and Fire Codes, National Research Council of Canada, Ottawa.

4. 1989 Survey of Airtightness of New, Merchant Builder Houses. Haysom, J.C., Reardon, J.T., and R. Monsour. Indoor Air '90: The Fifth International Conference on Indoor Air Quality and Climate, v. 4, Toronto, 1990.

5. Residential Air System Design. Heating Refrigerating and Air-Conditioning Institute of Canada (HRAI), Islington, ON, 1986.

6. Complying with Residential Ventilation Requirements in the 1995 National Building Code. Canada Mortgage and Housing Corporation, Ottawa, 1996.

7. Airtightness and Energy Efficiency of New Conventional and R-2000 Housing in Canada, 1997. Canada Centre for Mineral and Energy Technology, Natural Resources Canada, Ottawa

Help

Monday, May 7, 2012 by Customers Sharing Stories
Hi there, I live in South Africa and in winter the humidity levels can drop to 9%. The only humidifiers we can get are the cheap ones from the pharmasy that dont work or create white dust on all your furniture. I have a 300m2 home and I would love to humidify the whole home. I dont have any ducting, we have airconditioning which are split units. Can I install ducting for your product? I would like to have a controlled unit in each room. Also please let me know if your products are available in South Africa, if not can we purchase online and ship to SA.

Name: Colin
City: JHB
State: South Africa

Summer time use of my Aprilaire Humidifier Model 700?

Tuesday, April 24, 2012 by Aprilaire Team
Consumer question:
 
I recently moved into home that has Aprilaire Automatic Humidifier Model number 700. My question is during the Summer time when I switch the heat off and turn on the A/C at the thermostat. Will the Humidifier stay off or do I need to somehow turn the unit off?
 
Aprilaire response:
 
Thank you for contacting Aprilaire.

To live in Indiana, the humidifier would typically not bother to come on during summer, as nature gives us more humidity than we need. Any time the level of humidity is higher than the selected level, (or max of 45%) the humidifier will not come on.

Some people, just to make sure, will go ahead and turn down the humidistat to 'off' or at least the lowest setting. Then, for the same reasons as listed above, the humidifier will not come on.

Please let us know if you have any further questions.


 
 

 

Summer's High Humidity Affects Indoor Air Quality

Monday, April 2, 2012 by Aprilaire Team

Summer is almost here and with it we welcome the long-awaited warm weather but not the sticky, high levels of humidity that often come with it.  High humidity affects the quality of indoor air and can affect the health of you and your family in a variety of ways.

High humidity levels can cause mold, encourage dust mites which are a major cause of allergies, and cause a hot of problems in the home that can affect your physical health.  Visible signs of high humidity levels include condensation on windows, peeling wallpaper, damp patches on walls and ceilings, a musty smell and dampness.  But there are also numerous problems that go undetected because you can not see or smell them. 

A few of the most common health effects of too much moisture in the home include the following:

Dust mites:  At least 10 percent of the population suffers from a dust mite allergy.  Half of American homes have enough bedding with enough dust mite allergen to cause allergies.. Of these homes, 24 percent had levels that were five times greater than the threshold to cause allergic reactions.

To control dust mites, experts recommend regular cleaning to reduce dust, as well as encasing mattresses, box springs and pillows in allergy-free cases.  The more dust-free the home, the less likely it will be able to support significant populations of allergen0causing dust mites.  Some of the symptoms associated with it include sneezing, itchy, watery eyes, nasal stuffiness, runny nose, stuffy ears, respiratory problems, atopic dermatitis and asthma.

Bacteria: you can't see or feel bacteria but they live on countertops, table surfaces, carpet, pillows, mattresses and just about anywhere people are.  Bacteria also grow profusely when there is plenty of moisture present.

Formaldehyde: When humidity levels are high, products such as furniture, cabinets, building materials and even some latex paints then to release formaldehyde into the air at a faster rate.  Studies have suggested that people exposed to formaldehyde levels ranging from 50 to 100 parts per billion for long periods of time are more likely to experience asthma-related respiratory symptoms, such as coughing and wheezing.

If you suspect that the air in your home is too moist, be sure to vent the areas that create moisture, like the show or bathroom.  You may also consider a whole home dehumidifier like the Aprilaire Model 1710A, 1730A,1750A or the 1770A.  The Aprilaire dehumidifiers can work independently or in tandem with the heating and cooling systems to remove extra moisture from your home.  A system like this will allow homeowners to achieve the EPA recommended humidity levels in the house of 30-50 percent.

Aprilaire Periodic Preventative Humidifier Maintenance

Monday, April 2, 2012 by Aprilaire Team

Periodic Preventative Maintenance

  • NOTE: Periodic inspection and preventive maintenance of your total heating system is important for efficient and safe operation. Your heating contractor should include humidifier service at the same time. All models are equipped with an in-line water strainer and orifice as shown below. These parts should be inspected and cleaned periodically to assure continued proper unit performance.

Aprilaire Humidifier Recommended Annual Maintenance

Monday, April 2, 2012 by Aprilaire Team

Recommended Annual Maintenance

  • The water panel should be changed once a year, with a few exceptions.
    • The model 400 has a panel that should be changed twice a season
    • If extremely hard water is used in any Aprilaire humidifier, the panel should be changed more frequently than once a season. 
    • The water panel cannot be cleaned because it has a special coating that helps the water adhere to the panel while the air is passing through it.  Without the coating, more water will go down the drain and less will be converted into a vapor.
  • Drain line
    • Detach the drain line from the drain spud at the bottom of the unit. 
    • Bend it at the various points to loosen calcium deposits which may have formed on the inside of the line, and flush it with pressurized water. 
    • You can also pour bleach through it prior to the water.  This will kill any micro-organisms that happen to be living in the drain line. 
    • The drain line can be replaced should it prove difficult to clean. 
  • Feed tube
    • Detach the tube from the nozzle at the top of the unit, and unscrew the end of the solenoid valve at the other end of the feed tube. 
    • Run high pressure water through the tube and replace. 
    • When reconnecting the feed tube, remember to double wrench the connections to prevent leaking.
  • Inside of unit
    • Look for any mineral deposits on the Scale Control Insert after removing the water panel, and get rid of them by wiping the insert with a damp towel or rag.  They should come right off. 
    • If there are deposits on the inside of the cover, or in the case of a 700, on the fan blade, it may be indicative of a larger problem known as entrainment.  ()
    • Do not remove granulated coating on the distribution tray – not an issue with the new ones. 
      • The granular coating is there to break up the surface tension of the water.  This allows water to flow evenly through all of the openings in the water distribution tray. 
      • The newer trays have a fabric along the bottom of the tray which does the same thing as the granular coating.  The difference is the customer doesn’t have to worry about scraping off the fabric.
  • Hard or Soft Water
    • Aprilaire offers total flexibility in the installation of our humidifiers in that they will operate properly with either hard or soft water. Connecting to hard water may leave mineral deposits on the water panel that are scaly and hard in nature. Connecting to soft water may leave mineral deposits that are fluffier in nature. The bottom line is the water panel will typically last a full heating season using either type of water.  When extremely hard water is used in the humidifier, maintenance should be performed approximately every six months. 

Summer Aprilaire Humidifier Shutdown

Monday, April 2, 2012 by Aprilaire Team

Annual summer shutdown for bypass models 400 series, 500 series and 600 series close the bypass damper, which is a part of the humidifier, with the small damper handle.

Humidifier Contol:

Digital Humidifier Control in Automatic Mode (See Figure A):

No adjustment is necessary.

 

Digital Humidifier Control in Manual Mode (See Figure B):

Set the knob to the "OFF" position.

Manual Humidifier Control (See Figure C):

Set the knob to the "OFF" position.

I Love Craigslist

Monday, April 2, 2012 by Tom Ruse

I have to admit I'm kind of a Craigslist junkie. Buying, selling, always looking for deals.

I came across this ad over the weekend and thought it was pretty cool. In case it's too hard to read in the picture, it says:

Room humidifier - $10

I'm selling a room humifier that comes with several fragrances. You can run it with just water or with water and a fragrance. It has been used a total of about five hours, but now that we have an AprilAire system, we don't need it. It's still in great shape.

Thanks for looking."


 

 

 

Hard or soft water, any concerns?

Monday, March 26, 2012 by Aprilaire Team

Consumer question:
 
 I have a model 600 Aprilaire humidifier and I didn't see it listed in the FAQ's. Will operation of the humidifier while the water softener is going through it's cycle (backflushing,rinsing, brining) cause problems with either?
 
Aprilaires' response:

Thank you for your email regarding your model 600M Aprilaire humidifier. All of our Aprilaire humidifiers will function with hot, cold, soft or hard water. The water softener going through it's cycle (backflushing,rinsing, brining) will no affect on the operation of the model 600. The two can operate together or independent of each other.