Atlanta Air Conditioning Guide: Indoor Air Conditioning Components

Monday, May 21st, 2012

Air conditioning in Atlanta is a modern convenience that we can easily take for granted as long as all the parts are working well.  In every unit, no matter the size, the basic process is one of extracting heat from the conditioned space and moving it to the outside, leaving cool air in its place.

This process easily divides into indoor and outdoor components.

Air Conditioning 101

Based on the principal of thermal energy which states that heat gravitates toward cooler temperatures, compounds known as refrigerants are moved through a closed loop system, repeatedly contracting and expanding between liquid and gas forms, alternately releasing and absorbing heat along the way.  The particular chemicals are selected for their abilities to transform from one state to the other at low temperatures.

While the refrigerant evaporates into a gaseous state within the looped system, it absorbs heat, removing the stale air from the space being conditioned and evacuating it to the outdoors. The warm air is pulled through ducts to meet with the cooling loop.

Ductwork

The cooled air is distributed through ducts or tubing and released into individual spaces.  Additional ductwork is required to remove the stale air and pull it back to be reconditioned as it passes over the loop containing the refrigerant.  The air is moved in both directions by a blower, usually electric and sized to handle the amount of air no matter the building.

Ductwork is also sized to handle appropriate volumes of air. To maintain efficiency, large trunks distribute along central lines to smaller ones reaching farther out. The return air is usually taken from common areas.

The grates are found in the walls, floors and often as part of the dropped ceiling. When combined with a forced air heating system, the total energy use is much more efficient.

Looped Coils

The refrigerant is enclosed in a loop where it can expand and contract to make its transformation from gas to liquid and back again.  To change into a heat-absorbing gas, it travels through the evaporating coils, an intricate series of delicate fins that meets with the ductwork to regenerate the conditioned air.

An exchange valve allows just the right amount of liquid refrigerant into the evaporator coils.  If there is too much, the tube is flooded too tightly to allow expansion of the molecules and room to attract the heat.  If too little, the process is inefficient.

Cool Maintenance

When set up and maintained on a regular basis, your Atlanta air conditioning system should function with little attention and over sight. To schedule a maintenance visit today, give Cool Air Mechanical a call!

 

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Stone Mountain Water Heater Guide: How a Storage Water Heater Works

Wednesday, March 7th, 2012

For decades, millions of Americans have used storage water heaters to heat and store hot water for future use, including many people in Stone Mountain. These tanks are very simple and in many cases have become much more energy efficient, but you probably are wondering how they actually work.

The Basics

A storage water heater is exactly as it sounds. A large volume of water is funneled into a storage tank of between 20 and 80 gallons and heated for future use. When you turn on a hot water tap, water from the top of the tank is removed through the hot water outlet and cold water enters the tank through the cold water inlet – replacing the displaced volume and heated by the gas burner beneath the tank.

Water heaters can be electric, gas, propane or oil depending on what is available in your area. When the water temperature falls (as hot water is pulled from the tank), the thermostat opens and the gas burner ignites, heating the water until it reaches the preset temperature of the thermostat and it closes.

The Tank

When a tank is turned on, it is constantly heating the water supply. As a result, standby heat loss occurs. However, modern tanks are being built with exceptionally high insulation ratings (up to R-25) to minimize the loss of such heat. Additional heat loss occurs in gas and oil water heaters that must vent fumes and gasses through an internal flue. Fan assisted gas tanks and sealed combustion tanks reduce this type of energy loss in gas water heaters.

 Determining the Best Water Heater for You

If you want a new water heater for your home, make sure you do your research and learn what types of water heaters will minimize heat and energy loss without reducing your comfort level. Modern tank water heaters are surprisingly efficient, but only certain ones. Cool Air Mechanical can help you determine which option is best for you.

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Ellenwood Heating Repair Question: What Does a Furnace Thermocouple Do?

Monday, February 6th, 2012

Modern appliances are equipped with an array of safety measures to make sure that they operate safely in your Ellenwood home. This includes gas furnaces, which are harmless when working correctly but can be unsafe if something goes wrong. Perhaps the most crucial safety feature of a gas furnace is the thermocouple, also called a flame sensor.

Essentially, a furnace thermocouple works as a kill switch to shut off the furnace in case the gas is not igniting, like if the pilot light is out. Here is how it works.

The thermocouple is made up of two pieces of metal which are welded together at one end, called the “hot end” because it actually sits directly in the path of the furnace flame. On the cold end, it is wired to a circuit. Under normal circumstances, when the furnace is switched on, gas flows through the line and is ignited by a pilot light, ignition spark or glow coil. The flame heats up the thermocouple, and the furnace stays on.

However, sometimes the gas may not ignite, for example if the pilot light is out or the glow coil is faulty. In these cases, if there were no thermocouple, gas would continue to flow out without being lit, creating a very dangerous, poisonous and potentially lethal situation.

What the thermocouple does is detect heat, so if the furnace is on, but the hot end of the thermocouple has not heated up, that circuit up at the cold end kills the power to the furnace so that gas cannot continue to flow out unchecked. That way, you do not have to worry about a gas leak building to dangerous levels without being aware of it.

Sometimes, the thermocouple can malfunction, causing the furnace to shut off even if the burners are working just fine. Usually that is just the result of build up on the hot end over time, which can be fixed with some sand paper or emery cloth. If you think you have a problem with your thermocouple, give Cool Air Mechanical a call!

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How to Maintain High Efficiency Filters to Reduce Stress on Your Heat Pump: A Tip from Stone Mountain

Wednesday, November 23rd, 2011

The filter on your heat pump is an integral part of your Stone Mountain home’s comfort system. Without that filter, the device will quickly be subjected to an influx of debris and contaminants that can get into the machinery and the air being filtered into your home. As a result, you need to make sure you properly maintain the filters to reduce stress on your heat pump.

Change Your Filters

High efficiency filters are designed to remove as much of the airborne contaminants in the air as possible. This is fantastic for keeping your indoor air clean. But if you don’t properly maintain the filter, air quality can worsen and your heat pump is put under unnecessary stress. Specifically, the extremely tight knit filter, designed to stop nearly anything from getting through, gets clogged.

Now your heat pump is forced to work much harder to draw the air it needs from outside and heat or cool your home. On top of that, the filter is filled with contaminants that can start to leak back into the air supply, actually making your indoor air quality worse than it would be otherwise. That’s why it is so important to clean your filters on a regular basis (for permanent filters) and replace them if they are one time use.

Recommended Filters

You have options as to which types of filters you use for your heat pump. Filters come in multiple options, from super high MERV rated filters that trap up to 99% of all contaminants as small as 0.3 microns.

Electrostatic filters are especially efficient because they extract contaminants of all types – from dust and mold to smoke and gas fumes. A good filtration system should effectively remove anything from the air without needing replacement too often.

Permanent filters tend to offer the best protection against airborne contaminants and generally need to be cleaned once a month. HEPA filters are often permanent and while each filter is different, these are often extremely effective at minimizing contaminants in the air without putting stress on your heat pump.

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