Algae Growing on Your A/C? Causes and Tips for Removal

Algae Growth in AC Drip Pan Can Damage Home

Some homeowners are unaware that water from their air conditioner can cause extensive damage to their home. An air conditioner cools and dehumidifies the home. The dehumidifying occurs when the moisture-laden air in the home passes through the evaporator or cooling coil. The moisture condenses on the cold coil and drips into the evaporator drip pan. A drain line carries the water to the sewer. This line may be rubber, metal or plastic.

Algae Grows in Warm, Stagnant Water

This works fine, unless the drain line becomes plugged. The opening into the drain line or the drain line itself can become clogged with rust, debris or algae. Algae tends to grow in warm, stagnant water. When the drain line is plugged, the water will overflow the drip pan and spread to the surrounding area. The drip pan is usually about one inch deep and overflows quickly.

Many cooling coils are located in the air plenum of the furnace in the basement. If the floor in the furnace room is concrete that slopes toward a floor drain, there is no serious problem. The overflow will run out the drain. In the absence of a floor drain, the water could spread over the whole basement and ruin carpet or floor covering.

Many Air Conditioner Air Handlers Are in Attics

With the cooling coil located in the furnace, the furnace fan circulates the cooled air throughout the home. In the absence of a furnace, an air handler unit containing a fan is used to circulate the air. To save space, it is often installed in the attic. In this situation, a plugged drain line would result in costly damage to attic insulation and to the ceiling. If repair is not immediate, floors and carpet would also be damaged.

Some homes, especially in warmer climates like that of Palm Beach county, have a combination heating and air conditioning unit located outdoors. The fan or air handler is located inside the unit. A plugged evaporator pan drain line would not cause damage inside the home, but the leakage is undesirable. It would create a wet area around the unit. Water accumulation inside the unit will cause rusting, and bacteria and spores from mold and algae will be circulated throughout the home. This can cause respiratory diseases and poor indoor air quality.

Window Air Conditioners are Not Immune to Plugged Drains

Window air conditioners can have the same problem. Their drip pans and drain lines need the same treatment as a central air conditioner in spite of its location, size, and installation. Although the pan overflow may not drain into the home, bacteria and mold spores can be circulated into the home as the air is pulled in through the A/C unit.

Regular Maintenance Can Largely Prevent Drip Pan Problems

Cleaning the drip pan and drain regularly is a good idea. Before opening the cover of the evaporator coil, always shut off the main power supply to the unit. Do not rely on the interlock switch on the door. Pour water down the drain. If it runs out slowly, the drain is partially plugged. Clean any debris from the pan. A liquid algaecide may be used for cleaning, but a strong solution of laundry bleach is highly effective for cleaning the pan and drain line. After cleaning, flush thoroughly with water. Do not mix bleach with other cleaners, as toxic chlorine gas can be released. After a thorough cleaning, algaecide tablets can be placed in the pan to inhibit algae growth.

The drain line must slope all the way to the drain. A loop that would hold stagnant water encourages algae growth.

When the technician performs routine checkups, be sure the drip pan and drain line are checked. Routine inspections by a certified air conditioner technician and minimum attention by the homeowner can virtually eliminate the possibility of disastrous water leakage of your central air conditioning system.

Tips for Buying Air Filters: Arrestance, Efficiency and HEPA

Whether it’s for your air conditioning unit, your air purifier or just your vacuum cleaner, choosing the right air filter is important to its performance. Most big-box hardware stores have shelf after shelf to suit practically every need and requirement, but the sheer amount of choice can be overwhelming. With so many air filters on the market to pick from, how do you know you’re getting the right one?

There are three key terms you need to be aware of during the selection process:

  1. Arrestance – How well a filter removes large particles such as dirt, hair, dust mites and lint from the air.
  2. Efficiency – How well a filter removes microscopic particles such as dust, pollen, mold, bacteria, and smoke from the air.
  3. HEPA – A high-efficiency particulate arrestance, or HEPA, filter conforms to the stringent guideline of removing 99.7 percent of particles – 0.3 microns or greater – from the air.

Almost all air filters are graded, listing a percentage of particles removed, using the above criteria.

Some other factors to consider when buying an air filter are:

What will the air filter be used for?

Not all air filters are created equally, and different devices and units have different requirements. HEPA filters can be found for a variety of machines, but are generally hard to come by for residential air conditioning units.

What size filter do you need?

One of the most common errors to make is not knowing the size of air filter you need before heading off to the hardware store. As helpful as the staff may be, it’s not something that should be estimated. A good trick is, once you’ve assessed the size you need, write it down either on the filter frame if available, the unit itself or as a note in your wallet so you have a go-to measurement at hand for next time.

What level of filtration do you require?

There are four rudimentary levels of filtration for most store-bought air filters:

  1. Basic – collects large particles like household dust, dust mites, lint, pet dander and pollen.
  2. Good – collects all Basic level particles plus bacteria and mold spores.
  3. Better – collects all Good level particles plus smoke, pollution, microscopic allergens and many virus-carriers.
  4. Best – collects all Best level particles plus odor-carrying particles.

*Most filters above Basic level are also electrostatically charged for optimal particle hold.

Will it need to be incinerated when you’re done with it?
The vast majority of air filters have the advantage of being either disposable or washable ones that you can reuse, but if you require a filter to separate out toxic or dangerous substances then it usually needs to be destroyed via incineration. In such a case, be sure to select a filter without metal components so it will burn easier.

Quick Reminders:

While UV light devices may claim to eliminate bacteria and certain particles, making your home healthier and cleaner, they can’t get rid of everything and are no substitute for a good quality air filter. Also, when choosing a new filter, remember that carbon is key if you want to remove odors and VOCs from your home. Keep in mind that a mere few ounces of carbon may not always do the trick, and that the best filtration units use much more.

SEER Air Conditioner Efficiency Standards for Lower Electric Bills

A “seasonal energy efficiency rating,” also called a “SEER,” is a measure of an air conditioning system’s efficiency. By stating the average electricity consumption of an air conditioner during a typical “air conditioning season,” the SEER system allows consumers to more accurately estimate their energy usage than older rating systems allowed. A higher SEER indicates that an air conditioner uses less energy than those with a lower SEER.

For its calculation, a SEER assumes an air conditioner will be in use 1,000 hours per year, which represents eight hours of usage per day for 125 days during the course o/ds significant savings; upgrading from a SEER 9 system, which was previously a common rating, to a SEER 13 system will reduce electricity consumption by a bit over 30 percent. Upgrading from SEER 9 to SEER 16 will reduce energy consumption by nearly 45 percent. While exact savings depends on several variables, most homeowners will see an electricity bill reduction measured in hundreds of dollars per year.

To achieve a higher efficiency, manufacturers use thicker, more efficient metals in their air conditioners. Further, higher rated units generally have multiple compressors and larger coils. This raises the cost of the air conditioning system, so consumers must balance the cost of the unit with their expected energy savings. Most consumer guides recommend purchasing a system with a SEER of at least sixteen.

Additionally, air conditioning units degrade over time. An old unit which had a SEER of nine when it was first installed may currently be operating at a lower SEER. Air conditioning units today tend to retain their rating longer, but it is worth noting that the more expensive materials used in more efficient systems can be expected to help maintain the unit’s rating longer than less efficient systems.

And for those who seek to reduce their impact on the environment, a system with a higher efficiency rating helps reduce energy-related pollution. Systems with a higher SEER will also last longer and reduce the amount of material that ends up in a landfill.

At one time, those looking to purchase a new air conditioner had no means to calculate the energy cost of their purchase; manufacturers had no incentive to focus on efficiency over cost. The SEER system has provided consumers with a valuable tool to calculate the true cost of their new air conditioner.