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It's easy to forget about in-window air conditioners and central air systems over the colder months, when they're idle. That's why it's so common to to turn on the unit on the first sweltering day of the year only to discover it doesn't work.

But once you understand your own air conditioning system and learn what happens to it in the off-season, you'll appreciate how important it is to clean and maintain it for optimal use. And now's the perfect time to tend to your air conditioner -- before the first heat wave of summer comes swooping in.

Let's see how each of these air conditioning systems differ -- and how repair and maintenance is surprisingly similar.

WINDOW AIR CONDITIONING UNITS
Window units, often referred to as room air conditioners, are designed provide enough cooling for one room (or two, depending on the size). Most of these smaller units plug into a standard household electrical outlet. Larger units might require their own circuit and specialized wiring.

The room air conditioner pulls hot air from inside the room and cools it internally, releasing the heat outside of the house. This cooling process involves refrigerant gas, compression, heat absorption, condensation, coils and a fan which blows the cool air into the room.

Regular maintenance of your window air conditioner is important. Cleaning the filter and coils is a crucial part of the yearly maintenance regime, though some professionals recommend cleaning the filter every three months. Depending on your climate and how hard your unit is working, you might want to consider doing it more often. Here's how:

Clean The Filter
1. Unplug the air conditioner.
2. Remove the grill with a screwdriver to access the filter.
3. Remove the filter.
4. Soak it in soapy water for 5-10 min.
5. Rinse the filter and let it dry.

Clean The Coils
1. Unplug the air conditioner.
2. Take the unit out of the casing, setting it outside.
3. Spray the coils lightly with a hose.
4. Apply a natural all purpose cleaner directly to the coils.
5. Rinse and let it dry.
6. Cleaning the evaporator and condenser coils can be done even more regularly by vacuuming them. It is recommended that you do this monthly during the conditioner's working season.

CENTRAL AIR CONDITIONING UNITS
Central air conditioning systems are designed to cool the entire home. They're usually connected to the household's heating system, and share the same ductwork. A central air conditioning unit is made up of a condenser unit and evaporator coils. The condenser is mounted outside the house, where it pulls in hot air and delivers it to the evaporator coils, which cool the air and release it into to each room through a fan-coil and ducting system.

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For most HVAC maintenance tasks, it's highly recommended that you call in a professional. In fact, you should make an appointment to have an HVAC pro inspect your system before you begin using it each year -- right around the start of spring.

But even if you call in the pros once a year, your central air system can still benefit from periodic DIY cleaning. For starters, you should change the HVAC's furnace filter about every three months; this will cut down drastically on dust and allergens in the home. You can also clean your condenser and evaporator coils throughout the year (providing you can access them; some evaporators are protected by a sealed sheet metal plenum -- the part right above the furnace, which you should not remove).

(Safety note: Be sure to shut off power to the condenser and evaporator coils before touching your HVAC system. The shut-off box should be located on the exterior of the house, near the condenser.)

Cleaning the Condenser
A lot of dirt and debris can build up inside your condenser, since it spends all of its time outdoors. Remove the motor's cover, and you'll see the a fan and a coil. The fan's blades suck in air and pass it through the condenser coil. In the process, the coil gets clogged with dirt, leaves, grass, and other debris. Remove the debris and clean the coil with a dry rag. You might also consider using condenser coil cleaner from your local home improvement or hardware store. Just don't use water; it can turn dirt into mud, further clogging the unit.

Cleaning the Evaporator

Before you set out to access the evaporator, make sure to shut off power to the furnace. The switch will be mounted near the furnace, or on your main electrical panel. Inside the plenum -- the portion right above the furnace -- is the unit's evaporator. If the plenum is sealed with sheet metal, leave this task to an HVAC professional. But if you can access the evaporator and its coils, use your vacuum cleaner's soft brush attachment or a stiff brush to sweep away dirt.

Prevent Freezing
As discussed previously, air conditioners are prone to issues over the winter months. Freezing in particular may be plaguing your air conditioning unit. Frost build-up on the coils or ice in the ducts are both problematic in the cold months and can cause damage when not cared for. Some of these problems are easy to fix, while others require a professional. Do the investigative work yourself, and proceed accordingly.

Preventing your unit from freezing is much easier and less expensive than repairing it. Use the following method to prevent freezing in central systems. Perform the checks yearly, but when maintained properly you shouldn't notice deterioration more than every few years.

1. Carefully inspect the pipes, paying particular attention to any connecting spots.
2. Run a humidifier in the area that houses your unit; if moisture condensates anywhere on the cold air line, this indicates inadequate insulation.
3. Wipe any moisture off the piping with a towel.
4. Ensure that insulation covers the entire pipe, and either reinstall or increase the insulation anywhere that moisture condensed during the humidifier test. If there are any areas without insulation or where it has been poorly repaired, replace that section.
5. Use electrical tape, not duct tape, to seal the insulation.
6. Check the air conditioning line and venting system for any damage and replace sections as needed.

Troubleshooting

Sometimes you can hear that the central system is running, but it isn't cooling. The problem could be a dirty filter, or debris build-up on the outside unit. Keeping your outdoor unit free from debris is a challenge in the winter and spring months, but along with preventing rotting leaves and branches from building up, it will prevent the main unit from rusting.

If your air conditioner's performance is inconsistent, it may be time to replace the thermostat. If the air conditioner is loud or not blowing the air very well, you likely need to tighten the fan blades or otherwise repair it. For other issues, this troubleshooting chart is a useful tool for repairing common problems with your window unit.

Add cleaning and maintaining your air conditioning system to that lengthy spring cleaning list. Your summer self will thank you!


  • Capwhan

    Very useful article.

    Reply
  • gerryg

    "The room air conditioner pulls hot air from outside and cools it internally. This cooling process involves refrigerant gas, compression, heat absorption, condensation, coils and a fan which blows the cool air into the room."

    That statement is INCORRECT. An air conditioner removes heat from the interior space to the outside using a refrigeration process. An air conditioner REMOVES HEAT. It's similar to putting a hot item inside your refrigerator which removes the heat and transfers it outside the refrigerator through the condenser coil that is often on the back of the refrigerator. A heat pump or reverse cycle air conditioner provides heat to the interior space by removing heat from the outside air and transfers it to the interior space using a refrigeration process.

    Reply
  • walter

    The article said it pulls warm air from in the room and sends it out.


  • kaykells

    Read the article and you will see that is what it says - The room air conditioner pulls hot air from inside the room and cools it internally, releasing the heat outside of the house. It removes heat from inside and releases it outside. The cooled air is returned and the hot air is taken to the outside. Soem people just do not read....like you.


  • sam

    I don't know where you're reading, but I see this statement in the article and it is CORRECT.
    "The room air conditioner pulls hot air from inside the room and cools it internally, releasing the heat outside of the house. This cooling process involves refrigerant gas, compression, heat absorption, condensation, coils and a fan which blows the cool air into the room."


  • gmfr

    Where are the coils and what do they look like? Can you post pictures?

    Reply
  • C

    That's what I was thinking. I have never seen the coils, and dio not know if I would recognize them.


  • bill

    grate a no it all


  • gmfr



    Where are the coils and what do they look like? Can you post
    pictures?

    Reply
  • phil

    Gerryg is correct. Another poorly researched topic posted by AOL.

    Reply
  • sam

    ...you're wrong too! lol


  • Lyle

    gmfr Coils have tubes that are usually copper and the fins which can be very sharp and can easily be bent or flattened. Be gentle and careful. They should remind you of an auto radiator. One coil that has a fan lined up to draw air into and out of the conditioned room thru a filter is the evaporator or indoor coil. The other coil is the condenser coil which has a fan drawing outside air through the coil and then blowing it back outside. The indoor (evaporator) coil is usually protected by a filter and when the filter is removed is visable. The outdoor (condenser) coil is usually the surface you see on the outside of the unit unless it is covered with some kind of grille.

    Reply
  • Baggurte de Scuum

    "The condenser is mounted outside the house, where it pulls in hot air and delivers it to the evaporator coils, which cool the air and release it into to each room through a fan-coil and ducting system. " The condensing unit delivers no such thing to an evaporator coil. It removes coolant gas from said evap and condenses it to a liquid which it delivers to said evap. Get a clue. Thats why you dont see any ductwork on a condensing unit.

    Reply
  • Michael

    Sam and Baqqurt are both correct. Another good thing to do is add IceCold Synthetic Refrigerant
    Catalyst to remove oil fouling, improve transfer of heat coils by over 70%, evaporates refrigerent at a lower temp, colder air, reduce energy consumption from 15% to35%. Just to name a few of the benefits.
    Aloha from Hawaii.

    Reply
  • Emily from AbleAir-1

    Great article for homeowners. Another way to save money is to buy a programmable thermostat, which turns the AC down when you are not around. For more energy-saving tips, check out our recent blog post and feel free to borrow any tips for your blog! http://ableair1.sites.captico.com/2010/06/12/get-the-most-out-of-your-ac-this-summer/

    Keep up the great work,

    Emily from http://ableair-1.com

    Reply
  • Aircon

    Aircon - Aircon

    Reply
  • 16 Comments / 1 Pages
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