Choosing and Maintaining a Energy Efficient Air Conditioner Part1

Air conditioners are energy suckers, but buying the right one and maintaining it properly will ensure the energy consumption is kept to a minimum. Part 1

The summer season is upon us and with it comes heat. I don't know about you, but I do not like the heat. If it's over 75 degrees I feeling like I'm being cooked. I am a big proponent for energy efficiency and do not care for air conditioners all that much, but understand they are necessary, and do use them myself on occasion.

If you are using an air conditioner, or are needing to buy one, there are several things to consider. Many people buy air conditioners without understanding their operating principles, designs, and components. This is a huge mistake and can cost you money and frustration. I will break this down into several parts so you can confidently shop for your air conditioning unit or system.

How Air Conditioners Work

Understanding function will help answer many questions. The air conditioner uses the same operating principles as your refrigerator. Your home is cooled with a COLD indoor coil called a EVAPORATOR. There is also an outdoor coil that releases collected HEAT, and that is called a CONDENSER. Both of these coils are usually made from serpentine tubing that is surrounded by aluminum fins, much like a car radiator. Now, these 2 parts, the Evaporator and the Condenser are connected together and there is also a COMPRESSOR (Pump) which of course, pumps something! That something is the Refrigerant similar to your cars air conditioning system, but uses R22 instead of the automotive R134. Newer central A/C units may have something other than R22, which by the way is supposed to phase out by 2020.

These are the basic parts of an air conditioner. Certainly there is more to the A/C unit, but for understanding the operating

principle, this is what you need to know. It works like this: The Compressor (Pump) moves (pumps) the Refrigerant (a heat transfer fluid) through the copper lines between the Evaporator and the Condenser and through all those circuits of tubing and fins in the coils. The Refrigerant evaporates when it gets to the Evaporator (appropriate name!), and pulls (absorbs) the heat from inside the home. This hot Refrigerant (Gas) is then pumped back outside to the Condenser where the Refrigerant reverts back to a liquid dispensing it's absorbed heat outside the house. Think of it as a big circle. The Refrigerant is simply pumped around and around. On one end of the circle it absorbs heat, then on the other end, it gives it up! This is by no means a complete explanation, but I have put this into the simplest of terms so anyone can understand what goes on behind that plastic casing. Now you have at least a basic understanding, let's look at different types of air conditioners, and which one may be right for you.

Types of Air Conditioners

Due to the numerous potentials, what should you put aside and prepare for? Basic operating principles are all the same, but they certainly come in different configurations

Room Air Conditioners- Most people have seen these and use them. You will find them stuck in windows, through the side of a mobile home or house, and even on a rare occasion, in the back window of an old van. These air conditioners are meant to cool ROOMS, not homes. They are cheaper then central air conditioning, and usually less expensive to operate because you are cooling a small area, instead of an entire house. Small A/C units (less then 7.5amps draw) can be plugged into a typical electric outlet if not shared with other appliances. Larger units (greater then 7.5 amp draw) need a dedicated circuit,

usually 230 volts. You can tell immediately when you look at one in the store, because the plug will not be the typical plug you see on your everyday household appliance, they are much larger. Room A/C units have the advantage of being compact, targeted (one room), and cheaper.

Central Air Conditioners- Central A/C systems operate the same, but the cool air is circulated through a series of supply and return ducts that are usually located throughout the home. These ducts can go to floor registers, ceilings, walls, etc. Central A/C is very convenient for cooling an entire home. The sizing of these units is important to match the square footage of your cooling area. An under sized central unit will work hard and struggle. On the other hand, an over sized unit is a waste of money and will frequently cycle which can fluctuate the indoor temperature and wear out the compressor. You wouldn't buy a tractor trailer just to pull around your fishing boat!

Central air conditioning systems come in a couple different configurations.

Packaged Central A/C- In this system, the condenser, evaporator, and compressor are housed in one unit. This unit is usually placed on a rooftop or a concrete slab. Typical in small commercial buildings. The supply and return ducts go through the a wall or roof to connect to the A/C unit. It is also typical to package these units with electric heating coils or natural gas, which gives you central heat as well as central A/C. This eliminates the need for a separate indoor furnace.

Split System Central A/C- In this system the condenser and compressor our housed outdoors, and the evaporator is housed indoors, therefore, the split system. These are very common central units found in many homes.

All of these systems use filters. It's very important they are kept clean. Dirty filters cause restrictions, which creates more work for the A/C unit or system, therefore costing more money to operate. There is one more option for cooling that uses less energy, but definitely does not blow the ice cold A/C you might like. The operating principle is actually completely different as well, and these really can not even be called air conditioning units.

Swamp Cooler - Evaporative Cooler- These units operate by a process called "Evaporation", hah! appropriate. First let me state, these units are best used in low humidity areas. They are more energy efficient then their A/C counterparts, but do require a little more maintenance. The operation is simple.

They cool the air by evaporation. Your windows are opened part way to allow warm indoor air to escape as it's replaced by the cooler air. Think of the effect much like when your sweating. When you are perspiring, it cools your body. If you rarely use A/C, can get by without it, but would like a little cool on occasion, a swamp cooler may just work for you. If you are a DIY type person, or aspiring to be, you can easily build your own for cheap. Their operation is quite simple. We actually have a plan in our R&D shop for a really "cool" swamp cooler we'll be coming out with maybe by June.

Alright, you should have a pretty decent understanding of air conditioning operation and the types of units. Depending on your needs, and your expected comfort level, you should be able to narrow down your choice of air conditioning units to at least a central type or portable window type. If you choose a central, you will want to talk with your potential installer regarding proper sizing and exact type. If your a DIY type person,familiar with A/C, and have the necessary tools, you can easily install one yourself. There are many variations and possibilities even though they all operate with the same basic principles.

Energy efficiency should always be a concern, then dependability, then cost. If your shopping on cost alone as your first priority, then buy a window unit and forget the central system. The central A/C is a permanent installation in your home and there will be no changing your mind once you install it. I would never advice shopping by price as number 1, it should be number 3 on the list. More likely than not, you shop cheap, you get cheap, and all the headaches that come with it. Shopping with a budget, is not the same as shopping cheap. Continue article with part 2

I hoped you've learned something from this article. You will need to read part 2 to complete the article as I could not fit the entire article within submission guidelines.

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