Automatic Controls for Electric Furnaces

The automatic controls used in an electric heating system are designed to ensure its safe and efficient operation. This section is primarily concerened with outlining the operating principles of the automatic controls used with an electric furnace. These controls include room thermostat, thermostat heat anticipator and timing sequences. In a central heating system, the wall-mounted room thermostat is the control that governs the normal operation of the furnace. The operating principle is simple. The temperature selector on the thermostat is set for the desired temperature. When the temperature in the room falls below this setting, the thermostat will call for heat and cause the first heating circuit in the furnace to be turned on. There is generally a delay of about 15 seconds before the furnace blower starts. This prevents the blower from circulating cool air in the winter. After about 30 seconds, the second heating circuit is turned on. The other circuits are turned on one by one in timed sequence.

Use a heat pump thermostat or a conventional thermostat containing an electric setting to operate an electric furnace.

When the temperature reaches the required level, the thermostat opens. After a short time, the first heating circuit is shut off. The others are shut off one by one in timed sequence. The blower will continue to operate until the air temperature in the furnace drops below a specified temperature.

A typical room thermostat will have a fan switch, a system switch and a temperature selector. The temperature selector on the thermostat is used to select the desired temperature. The actual operation of the heating system is governed by the position of the fan and system switches.

Most room thermostats contain a heat anticipator. This is a device designed to assist the thermostat in controlling closer to the to the desired temperature range.

When timing sequence are used the current flowing through the first time-delay sequencer must also flow trough the heat anticipator. In order to obtain satisfactory operation, the heat ainticipator setting must be equal to the current draw of the sequencer.

The furnace manufacturer will generally recommend the setting for the heat aniticipator adjustment for each size unit. For example, this setting recommended for a Trane Model EUADH 07 electric furnace is .45. This thermostat adjustment will vary depending upon the type of time-delay sequencer used, the furnace manufacturer, and the size of the furnace. This may be illustrated by the recommended heat-anticipator setting given by Coleman for its furnace models. All Coleman 25-kW, and 20-kW furnace models require a heat ainticipator setting of .60.

After you have adjusted the heat anticipator to the suggested setting, operate the furnace several hours and observe the results. If there is insufficient heat, it may be caused by short furnace cycles. This can be corrected by moving the heat-anticipator pointer to a slightly higher setting. If there is too much heat, the long furnace cycles are overheating the structure. This can be corrected by moving the heating-anticipator pointer to a slightly lower setting. After making these thermostat adjustments, allow the furnace to operate several hours to determine whether further adjustment is required.

Atlanta HVAC Guide: Green Your Home Ideas

Written By: triadmechanical.com
Energy costs and depleted supplies force us to consider alternatives to how we lived 20 and 30 years ago. This transformation of thinking is most prevalent in our homes.  Not only are the habits of our lifestyles under consideration, but the very structure of our homes as well.  From materials to furnishings, houses are being transformed.

Remodel versus New Construction

The amount of open land available for development is less than before, so creativity is being utilized to design more compact developments, concentrating homes into multi-family structures and creating communities with shared spaces.
If you need more square footage for a growing family, staying put by increasing the footprint or adding a second story is viewed as more green than starting fresh on a new plot of ground.  In either case, careful consideration to the materials and heating systems used can have a significant impact on the environment.

Changing Habits and Habitats

From acoutrements to the house design itself, each decision to change an appliance or upgrade the finishes has greener impacts, no matter the choice of color.  Something so simple as converting light bulbs from incandescent to longer-lasting and more efficient compact florescents (the twisty tube ones) is becoming required in many communities and saves serious dollars in utility costs.
Hot water heaters can be combined with the boiler to share the energy.  More energy efficient glass can bring in more solar heat and light and hold it there longer.  Bamboo flooring only takes five years to grow, but can last 60, allowing our supply of trees to replenish.  Getting an energy efficient air conditioner can lower you energy bills during the summer.

Greening Your Home

Transforming the colors on our walls with odorless zero VOC  paints makes the chore fun to do yourself (instead of smelly and causing a headache), satisfying a need to feel accomplished and useful.  Composting left-over food to nourish our vegetable garden contributes to the effort of awareness far more emphatically than just flushing waste out of mind down the garbage disposal.

3 Sounds You Need To Listen For

Written By: Westland Heating & Air Conditioning Westlake, OH 

Our homes in Westlake make weird noises from time to time. This is to be expected. But the furnace in your home might be a different story. If you start to hear certain noises it might be a good idea to call for furnace repair services. At Westland Heating and Air Conditioning, we’ve responded to countless calls for furnace repair service in Westlake. So that our customers can have a better understanding of their furnace, we put together a few of the most common furnace sounds that should cause trouble.

Squealing

If your furnace makes a squealing sound when you start it up, you should probably call for service. This isn’t a life-threatening problem, but it can be annoying. This happens when the blower’s belt or bearings have worn out. This can be easily fixed by a professional Westlake heating technician.

Rattling

If you hear a rattling sound when you turn on your furnace this a very serious problem. While it might be that some screws are loose on one of the covers, it can also indicate a problem with your heat exchanger. The heat exchanger in your furnace has two jobs: first, to heat the air going into your home and second, to exhaust the harmful combustion fumes out of your house. When the heat exchanger cracks, those dangerous combustion fumes, that can include carbon monoxide, are blown into your home. Call your local heating contractor immediately.

Rumbling

If you have a fuel oil furnace and you hear or feel a rumbling when you start it up, this could be another critical problem. The cause of this is unburned oil in the combustion chamber continuing to burn after the unit is turned off. This could also leak carbon monoxide into your Westlake  house.

Roaring

If your furnace erupts with a loud roaring sound, like when you fire up a welding torch, this is a very bad sign. It means that there is an uneven mixture of fuel and air.

Furnace Fixes for the Handy Homeowner

Next time your furnace shuts down, check these five fixes before calling your Denver HVAC company . This trouble shooting guide will help you to repair your furnace yourself. Troubleshooting your furnace problems is worth considering before making a call for furnace repairs. These steps will show you and explain how you can diagnose and fix common furnace problems. Only you know just how handy you are consider your abilities before performing these steps safely and properly.
Proper furnace maintenance is the best way you can prevent common furnace malfunctions from happening. Furnace servicing should be carried out at least once a year. Even if your furnace was was installed professionally there are times when it will cease providing heat. The reason for the furnace failure could be anything from an airlock in the fuel pipe, blocked fuel inlet, or a problem with the controls. The following explains some of the most common issues you can fix on your own.

1. Check for leaky or blocked ducts that diminish airflow
If your furnace is running but there are cold rooms in the house, check to see if the registers are open. Next take a look at the ductwork you can access without trouble. Look for space between sections of the ducts and branching areas. If you find gaps seal the sections with foil tape. Finally check for handles, these are dampers, coming from the ductwork if you find any make sure they are open.

2. Change filters
Old dirtied filters are a common cause of furnace issues. Dust and grim hamper airflow and if the filter is too dirty is clogs and the heat exchanger will overheat and shut off causing your house to remain cold. A dirty filter can lower the efficiency and lifespan of your furnace. When the heater is running but heat is not going into any of the rooms in your house it's time to replace the filter.

Your owner's manual will show where the filter is located and what it will take to remove it. Changing flat filters monthly will help increase efficiency. All filters should be checked monthly. Checking the filter should be done by holding it to a light source. If you can see the light clearly it is time to replace the furnace. Most pleated filters will be OK to use for up to three months however you should change them more frequently if you have pets.

Insulating Materials: Building Construction and Location

Insulating materials are specifically designed to reduce the rate of heat transmission through ordinary construction materials to an acceptable level. A dry material of low density is considered a good insulator; however, in addition to this characteristic, it must also have a conductivity value of less than 0.5.

The conductivity value of a material is a purely arbitrary one determined by the amount of heat that flows in 1 hour through a 1 inch thickness of a material 1 square foot in area with the temperature exactly 1 degree F higher on one side of the material than on the other.

Air spaces, or air spaces bounded by either ordinary building materials or aluminum foil, also provide some insulation, but not to the degree formerly thought possible. Dead air spaces in building walls were once considered capable of preventing heat transmission in a manner similar to the space between the walls of a thermos bottle. Later research proved this to be a somewhat false analogy because the air in such spaces often circulates and transmits heat by convection.

Air circulation can be checked by filling the hollow space with an insulating material that contains a great number of small confined air spaces per unit volume. This stoppage of air circulation is what produces the insulating effect, and not merely the existence of the air space. Under these circumstances, it is obvious that the most practical method of insulation is to fill the area in the walls with a material containing these minute air spaces.

Several manufacturers produce insulating materials in a variety of shapes and forms for insulation in houses and other buildings. Frequently, instructions for the installation of the products will also be provided by the manufacturer. Local building supply outlets and lumber yards will often be very helpful, too, and will usually recommend the best way to install the insulation material.

Construction and Location
A masonry, common in many older homes, is a particularly poor thermal barrier. A typical masonry cavity wall has a thermal resistance equal to approximately 1in of ridged insulation. Exterior opaque masonry walls should have maximum U-value of 0.11, requiring insulation rated at R-7 or greater.

A new building (particularly a residence should be located so that the large windows in the main rooms face south to receive the maximum sunlight during the winter months. If possible, the building should be built in a location that offers some natural protection from the prevailing winter winds. Tight, well-insulated construction should be incorporated in the design of the building from the beginning. Although the initial costs will be somewhat higher, they will be effectively offset by the reduction in heating and cooling costs.

If a new Denver heating and air system is planned for an older structure, the existing insulation should be checked and, if necessary, repaired or replaces before the new system is installed. 

Important Air Duct Maintenance

The air ducts used in HVAC systems require very little maintenance other than periodic cleaning.  Most air ducts accumulate dust and dirt which can be dangerous as mold, fungi and dirt mites can grow in the warm dirty air ducts. Built up dirt can also become a fire hazard as it combustible materials accumulate in the ducts.  Air duct cleaning should be scheduled periodically to prevent these accumulations, especially if you live in a climate where you run heat and air conditioning.

Proper doors should be placed throughout your duct system to allow access for cleaning.  New access doors can be installed by a local HVAC company to allow you to clean your air ducts regularly.

You will want to check your ductwork for cracks, holes or other damaged areas causing leaks.  If you find cracks or holes in the return ducts you can be sure you're spending more on energy bills than necessary. If you try and patch up the cracks or holes yourself, you can almost be sure you will create a pressure imbalance in your system.  If you find cracks or holes, find a heating and air conditioning company that has experience fixing ductwork.

The last thing you want to check is the proper balance of air supply and return in your system.  You want to make sure the amount of air supplied to an area by the air ducts is equal to the amount of air returned to your furnace air handler.  An imbalance can draw allergens, dust mites, mold and other contaminants from your basement or attic into the rooms you are heating or cooling.

Rethinking Your Home Furnace

Posted on November 2, 2012 by Tracy Burleson

Guest Blogger: Valerie Hanneken, Social Media/Communications Specialist, Lennox Industries, Inc.


Advances in technology are not limited to new cell phones, computers and tablets. Innovation has changed the products of the heating and cooling industry as well. In the past, homeowners relied on a furnace to heat their homes as temperatures dropped. The furnaces of today can provide comfort while significantly reducing consumer’s monthly utility bills.


The Dave Lennox Signature Collection SLP98V furnace uses the latest industry-leading technology to improve efficiency and sound pressure levels. Recognized as aMost Efficient ENERY STAR Qualified Product, the SLP98V furnace meets or exceeds the U.S. Environmental Protection Agencyguidelines for energy efficiency, with more than a 98 percent conversion of fuel to energy.


The SLP98V also incorporates Precise ComfortTM technology, which automatically adjusts fan speed, heat and airflow to give the homeowner ultimate temperature control. AirFlexTMtechnology provides unique custom settings that allow the furnace to meet the specific year-round comfort requirements of any home.


When installed with the easy-to-use programmable Lennox icomfort Wi-Fi thermostat, the SLP98V furnace can exchange information with the device through “cloud” connectivity and make adjustments to optimize performance and efficiency. This means, consumers can control their furnace wirelessly from any Smart phone, tablet or computer.


Technology has changed the way heating and cooling equipment operates, and as a leader in the market, the Lennox SLP98V will certainly cause consumers to rethink the home furnace.


The Dave Lennox Signature Collection SLP98V furnace will be on display as part of the American Natural Gas and Propane Industries exhibit at the National Association of Home Builders’International Builders’ Show on January 22 through 24 in Las Vegas, NV. Make sure to stop by to learn about the SLP98V furnace, as well as other leading-edge natural gas and propane appliances.

What Makes an Efficient Furnace so Efficient

By Mike Meincke

With today's rising energy demands, volatile financial & housing markets and a constant potential of increased living costs looming over our shoulders, catching a financial break anywhere we can as a consumer should be of keen interest to everybody. 90%+ Annual Fuel Utilization Efficiency (AFUE) furnaces may easily provide the solution and can easily off set a household bill or two with all of the energy being saved by this furnace in contrast to the conventional 60-80% AFUE furnace that is more than likely currently in your home even as you read this article. 90%+ AFUE furnaces have a 2 heat exchanger design to avoid wasting heat, in the past the product was problematic when it was first developed in the 90's, but has since been improved to near perfection today by most manufacturers to be a very reliable product and if sized properly and installed properly will save an incredible amount of money on the utility bill that you can capitalize on year in and year out.

The two heat exchanger design is the key feature that allows a 90%+ AFUE furnace to operate so efficiently. A primary heat exchanger handles the ignition of the furnace and the natural gas fire (propane, kerosene, heating oil or what ever the furnace burns) of the furnace burners. As the burners are engaged inside of the heat exchanger, the heat exchanger gets hot so that when the furnace blower turns on, forced air travels over the hot heat exchanger to allow for heat transfer to occur, sending warm air through your air ducts and to ultimately heat the air in your home. With a conventional 60-80% AFUE furnace that is all that is present for a heat exchanger, but through brilliant engineering furnace manufacturers realized that flue gases always creates hot moisture that is typically wasted out of the flue pipe and so they decided to capture this free energy by designing a better product. So engineers went to work to produce the two heat exchanger furnace and incorporated a secondary heat exchanger that looks like a coil to capture the hot flue gas moisture to re use this heat in a more efficient appliance, rather than wasting this heat out of the flue pipe.

Remarkably after 70 years of relatively little change in the heating market in terms of how a gas furnace basically operated, a vastly more efficient appliance emerged on the market.

Typical HVAC Services offered by Local Contractors

posted by: Jeffrey Ahbe
If you're hvac system isn't working perfectly, you may consider calling a local contractor or HVAC company to take a look at your equipment.  There is nothing worse than having a problem with your heat when it's cold outside and you actually need it to keep your house warm.  The unfortunate thing is this is usually the case.  If you do not exactly know what is wrong with your HVAC system, here is a list of typical services offered by a Denver HVAC company and an average cost you can expect to pay:

HVAC Service Calls can vary in price depending on the time of year and how busy the company or contractor is.  Most of the companies in Denver range from $59 - $129 for their service call and vary in what that includes.  Many include the estimate, some include the first hour of the work and some will include the total credited towards your final bill.

Cleaning and Repairs can vary in the extent of the job and the price will depend on the amount of cleaning or repairs needed.  Some companies specialize in cleaning hvac equipment such as air duct and furnace cleaning. Other companies specialize in repair and do not offer cleaning services. 

New furnace or air conditioner installations are offered at affordable prices, especially if you buy the hvac equipment from the contractor or company.  An install for an air conditioner can be anywhere from $1800 - $6,000 depending on the unit you purchase.  An install for a furnace can be anywhere from $750 - $3800 depending on the unit you purchase.

Ductwork installation or or repairs are another popular service offered by hvac companies or contractors.  Many will offer both residential and commercial.  With many older homes, the ductwork was not installed efficiently so adding new or more ductwork can help heat or cool your home or office more efficiently.

5 Signs It's Time to Replace Your Furnace

Written By Jeffry Ahbe

There are several quick and easy ways to know when it's time to replace your gas furnace before it costs you cash or becomes unsafe. A efficiently working furnace is part of a healthy and cozy home environment. Your heating system should heat the home without using a large amount of energy or polluting the in home air quality. Knowing the warning signs of a heating system that is on the way out is important so you can avoid an all out crisis situation in your home. Learning that your furnace is no longer; working in the middle of a February blizzard could leave your family out in the cold. Denver furnace companies are often busy in the winter months and you don't want to be waiting for repairs in a cooling home.
Do you know the age of your furnace?
Knowing how old your furnace is will help you know about how much longer you should expect it to last. The average life span of a home furnace is 17-20 years. If your furnace is approaching it's late teens, you should start looking for it's replacement. Waiting until your furnace breaks down will necessitate a quick purchase which may not be right for you. One quick way to know if your furnace is getting old is to look for a pilot light. If you find one, your furnace is well past it's life span.

Has your burner flame changed color?
If you burner flame has changed from blue to yellow, it is a sign that carbon monoxide is being created by your furnace. Other possible signs carbon monoxide is present are streaks of soot around the furnace, moisture on windows and other cold surfaces, rusting on flues and appliance jacks, and leaking from the base of the chimney.

Common Furnace Repair Problems in Fairbanks

Written By Atrol Inc

Most home and business owners know one primary thing about their furnace: that it provides heat. Pretty basic, right?

Well, in a perfect world, it really ought to be that basic, because in that perfect world, your furnace or boiler would never break down. But since they do, and since they’re complex machines, sooner or later you’re going to need the services of a professional HVAC contractor.

Here at Altrol Heating & Cooling Professional Repair, we’re all about sharing information so our customers can have a better understanding how their heating and cooling systems operate, and what might be causing a problem. So, with that in mind, here are the most common repair problems we encounter: Thermostat malfunction, Tripped circuit breake, Blown fuse, Pilot light gone out, Furnace not generating heat, Temperature swings, Blower problems

Take care of your HVAC equipment through regular servicing

Written by Victor
Having invested in a home, you would want to make sure that you are able to live comfortably in it through different weather conditions. This is where various HVAC equipment or heating, ventilation and air conditioning equipment as they are better known, come in handy.

But just buying them is not the end of the story. You need to maintain your outdoor heaters, patio heaters and evaporative cooling systems well enough so that they always perform at optimum levels. While some of the basic maintenance can be done by yourself, you need to hook up with a specialist HVAC maintenance agency for regular inspection and any required corrective action. These agencies have the necessary personnel, testing equipment and professional attitude to do a good job so that you do not have to spend money later on to get certain parts and so on.

The maintenance that can be done by you includes using a vacuum cleaner to get rid of the accumulated dirt, along with any dust around the blower wheel and flue. Any build up of dust can hamper the smooth working of the motor and will drive up your energy costs. Changing of the filter is another task you should be able to manage and though this just takes a minute or two, most of us tend to ignore the monitoring and maintenance of this vital part. It is the filter that traps any excess dirt and prevents it from getting into the ducts of the equipment. Clogging of the filter will result in HVAC appliances such as a patio heater or outdoor heater to work much harder in order to be able to ensure circulation of air into the system. The result is that you will end up paying more in energy charges and the unit will also break. Hence either clean the filter regularly or change it if required to ensure smooth working of the unit. 

About the Author:
Celmec - international is one of the leading manufacturers of HVAC equipment. Visit their site http://www.celmec-international.com/ to know more about them.

Pre-Winter Furnace Maintenence and Repairs to Keep You Warm All Season

You weren't thinking of home maintenance while you were out enjoying the warmer months of the year, but the chilly season is here now- are you ready? There are some critical items to check before the icicle begin accumulating. Denver heating service professionals can perform routine maintenance can repairs helping to avoid chilling consequences. 

Having a professional clean and inspect your furnace annually will prevent the buildup of deadly carbon monoxide in your home.This inspection will check for damage as well as keep your family safe from noxious gasses. Having a Denver furnace repair professional inspect your furnace each year can help notify you of problems that, during cold months, could lead to frozen and burst pipes. 

Inspecting the furnace will involve checking a variety of components. The motor should be checked for worn bearings which could shorten its life. You should also make sure that the inside of the furnace clean so that the blower circulates clean air. Finally the burner should be inspected for wear and cleaned of ash or reside. Too much build up in this area causes the flame sensor to turn off which means the furnace will not light. 

If you have a gas burning furnace, the gas pressure should be inspected annually. If the pressure is too high or too low of gas pressure can cause the furnace’s flames to burn too hot or too cold. The furnace heats up and shuts down too soon or not soon enough. This leads to poor efficiency and shortens the furnace’s lifespan.You should also check your furnace system for blockages in your fuel or exhaust vents that can lead to build up of carbon monoxide. Vents can become blocked by nesting birds and rodents looking for a warm home.

If cold nights creep up on you before you think about your furnace, you may find yourself without heat on a frosty night. There is still time to act, call your Denver heating and air company for repairs before you're caught in the cold.

Keeping Your Home Comfortable with Heating and Air Conditioning Services

Without a heater or air conditioner in a home, the people living inside it would have to deal with the warm and cold weather throughout the year. While having these systems is going to make a home more comfortable, they have to be taken care of properly. Air conditioners and heaters need to have regular maintenance in order to stay working well. Denver heating and air conditioning services are  affordable, easy to get and will ensure these systems stay working correctly for a long time. Without regular maintenance there are a lot of things that can break down and need repaired. Some of the most important services to get for heaters and ACs include:

What Inspectors will check for when Performing Heater Maintenance Services:
1.) Thermostat 
When a service professional comes over to inspect a heating unit, they are going to look for a number of different things. First of all, they will make sure the thermostat is in proper working condition. This is important to look for because an incorrect thermostat could be wasting a lot of money throughout the year. 
2.)Vents 
From here, they will check to make sure air is flowing properly throughout the home and that all vents are properly opened. They may also inspect the condition of the filters to make sure they are in good shape.
3.) Pipes/Lines/Lights
The service professional will also look at fuses, wires, gas lines and the pilot light to make sure everything is in good shape. Most homeowners are surprised to find that they need to get small repairs done in order to make their heating system more efficient. These small repairs can prevent future damage and actually save money in Denver heating. In fact, if a service person finds there is a hole in a gas line, they could save the life of a family!

Do It Yourself Fall Furnace Maintenance

A good HVAC system depends on a good furnace and air conditioner to warm and cool your home. There are several things you can do as a home owner to maintain your machines work properly for a long time. As you will read, you will find many things to assure your furnace has a long life and free of future furnace repairs.

Your furnace is made up of several different parts. The blower and air filter being two of the most important parts. If someone is having a problem with their furnace, most likely they are having issues with their blower or air filter so it is important to check these each fall before your turn on your furnace. Your blower and air filter are generally cheap to repair or replace but if not maintained, it could cost you more than a thousand dollars to replace your furnace down the road. Make sure to add a new filter each fall and make sure your blower is moving without making any unusual noises and is pushing a strong amount of air into each room.

Your thermostat is also a part that needs to be checked regularly. It does not take a lot of time but can save you a lot of money down the road on your utility bill. There are several different types of thermostats. The programmable thermostats that let you change the temperature for different times of the day. If you are not home, the temperature in your home does not need to be toasty.

Typical Furnace Maintenance Recommendations

Furnace maintenance is extremely important to the life of your furnace; proper cleaning and repair will ensure that your furnace works its best and lasts as long as you own your home. Here are some tips to help you keep your furnace in good running order so that you don’t have to replace before its time.

Furnace Care and Maintenance
Start by considering your furnace filters – do they need changing or replacing? Furnace filters catch all the dust, debris and hair that run through your ducts and help to purify the heat that comes out of your vents. When the filter gets clogged, your furnace stops running as well and exerts more energy than necessary. In extreme cases, the blower may be affected, triggering the need for costly repairs. Replace your disposable filters as the first part of heating maintenance.

Schedule a tune-up yearly by a licensed HVAC repair specialist to keep your furnace in good running order. It’s a good idea to schedule this in early fall, before you have to turn on your furnace, to give you time to schedule any furnace repairs that need to be done. A technician will check your flues, ducts and temperature settings, examine your heat exchanger for cracks or other damage, and double-check all safety mechanisms to ensure proper furnace efficiency. HVAC maintenance should take place regularly if you want to avoid emergency furnace repairs.

Some HVAC technicians will offer furnace maintenance packages. It may be a good idea to look into these if you don’t feel up to maintaining your furnace yourself. If you are a do-it-yourselfer, you can keep your furnace running efficiently by checking your owner’s manual regularly. Tasks you can do yourself include checking to see if the blower motor needs to be lubricated, replacing frayed belts, checking for visible cracks or blockages, and more.

Proper furnace maintenance allows you to keep your furnace running longer and put off any expensive repairs. Always make sure to check your furnace annually for any of the problems mentioned above and keep your equipment in good running order.

How to Practice Safe Furnace Cleaning

When you are cleaning your furnace, three things should be cleaned:

• The filter system
• The blower
• The motor

Replace your furnace filter at the beginning of the heating season to keep your home cleaner and to keep dirt and debris from flying into your blower and ruining it. Check the filter by holding it up to the light. You’ll be able to see if it’s clogged just by looking at it. If it’s disposable, replace it. If it’s a permanent filter, follow the instructions on the side of your furnace to learn how to clean it.

Clean your blower by removing the panel that covers the filter to gain access to the blower or the panel on the front of the furnace. Slide out the fan unit to gain access to the blower and clean it out. If you are not comfortable doing this, hire a certified HVAC specialist to clean all three parts of your furnace for you. HVAC specialists have a complete range of experience with gas furnace cleaning, oil furnace cleaning, and electric furnace cleaning. It is a good idea to get your furnace serviced by a professional even if you are willing to clean it yourself.

Troubleshooting a Gas Furnace

By Bob Formisano, About.com Guide

The Conventional Gas Furnace
The conventional gas furnace (up to 89% AFUE) is an appliance looking like a large box that does the following:

• takes in cold air,
• cleans it with an air filter,
• heats it up with a gas burner using a steel heat exchanger,
• distributes the warm air with a blower motor through your home's ductwork

The heated air then cools down in your home's various rooms and returns to the furnace through return air grills and ductwork.The cold returning air enters back through the air filter into the furnace to complete another heating loop.
Sometimes there is a humidifier mounted on the furnace or the return air ductwork.
Furnaces come in different efficiencies measured in AFUE.
Once in a while things don't work quite right and you need to troubleshoot a gas furnace repair or relight a standing pilot if it has one. Conventional furnaces may have electronic ignitions which need special troubleshooting.

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