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Central heating systems have a primary heating appliance, such as a furnace, typically located in your basement or garage. All furnaces consist of four main components: 1) burners that deliver and burn fuel, 2) heat exchangers, 3) a blower and 4) a flue that acts as an exhaust for gaseous by-products. Depending on your situation, region and needs, you can choose from heating systems running on either gas or oil as fuel, or a hybrid packaged system that can use both fuel types.
Without proper ventilation, carbon monoxide can be lethal at concentrations of 1000 ppm (0.1%). However, at several hundred ppm, carbon monoxide exposure induces headaches, fatigue, nausea, and vomiting. Carbon monoxide binds with hemoglobin in the blood, forming carboxyhemoglobin, reducing the blood's ability to transport oxygen. The primary health concerns associated with carbon monoxide exposure are its cardiovascular and neurobehavioral effects. Carbon monoxide can cause atherosclerosis (the hardening of arteries) and can also trigger heart attacks. Neurologically, carbon monoxide exposure reduces hand to eye coordination, vigilance, and continuous performance. It can also affect time discrimination.[15]

Heating Repair Co


Ground source, or geothermal, heat pumps are similar to ordinary heat pumps, but instead of transferring heat to or from outside air, they rely on the stable, even temperature of the earth to provide heating and air conditioning. Many regions experience seasonal temperature extremes, which would require large-capacity heating and cooling equipment to heat or cool buildings. For example, a conventional heat pump system used to heat a building in Montana's −70 °F (−57 °C) low temperature or cool a building in the highest temperature ever recorded in the US—134 °F (57 °C) in Death Valley, California, in 1913 would require a large amount of energy due to the extreme difference between inside and outside air temperatures. A few feet below the earth's surface, however, the ground remains at a relatively constant temperature. Utilizing this large source of relatively moderate temperature earth, a heating or cooling system's capacity can often be significantly reduced. Although ground temperatures vary according to latitude, at 6 feet (1.8 m) underground, temperatures generally only range from 45 to 75 °F (7 to 24 °C).
Natural gas furnaces operate similarly to the above, using a pilot light to ignite the burners and heat up the air. Also similar to propane gas, your average repair costs for a natural gas furnace will range anywhere from $125 for small repairs to $1,200 if you have to replace the entire heat exchanger. The difference between both options is not necessarily the actual furnace, but the type of gas used to burn through it and heat your home. As a result, the repair costs tend to be close to identical.
*Residential Service call's subject to $119.00 travel and diagnostic fee, Commercial Service call's subject to a $149.00 travel and diagnostic fee. Once diagnosed, necessary repairs will be quoted in accordance with standard flat rate repair price. Repair and quoted repair price may be accepted or declined by the customer at that time. Travel and Diagnostic fee will still apply in case customer declines repair. All calls are C.O.D. Overtime rates for Residential Service are $169.00, overtime rates for Commercial services are $179.00.  These rates are for services performed after normal business hours Monday through Friday 8am-4:30pm.
Air Blue Heating and Cooling Inc. delivers 100% satisfaction guaranteed on all residential and commercial installation, service and repair projects. We offer a 2 Year Repair Warranty and a Lifetime Installation Guarantee. Every service is handled in an organized manner, with careful clean up at completion, and an end result that meets your highest expectation.  Through proficient workmanship and quality products, we trim energy costs and ensure reliability.  Through our commitment to excellence, we fulfill your everyday requirements with exceptional solutions.
We are service professionals! As licensed contractors and specialists in the field of heating and air conditioning, we have the tools, the equipment, and the experience to keep your equipment running smoothly all year long. If it is emergency service that you need we are available to assist you! To help reduce service emergencies, we offer service agreements to keep your comfort system running at peak performance.
Keeping a warm and comfortable home, without excessive cost, can be a challenge.  The professionals from Air Blue Heating and Cooling Inc. specialize in tough challenges.  As a Carrier Factory Authorized Dealer, we match your needs to superior products, bringing you precision temperature control with unprecedented efficiency.  We enhance the enjoyment of your living and working environment with convenient features, reliable operation, and minimized energy bills.  Whether you’re in need of installation, replacement, seasonal maintenance, or prompt repair, we provide same-day and 24/7 Emergency Service across Wheeling, Buffalo Grove, Northbrook, Deerfield, IL.  Our team of fully licensed, bonded, insured, and NATE-certified technicians work tirelessly to eliminate the stress, wasted time, and disruption of anything less than ideal temperature control.  By focusing on customer service and delivering trusted results, Air Blue Heating and Cooling Inc. takes all the necessary steps that lead to your 100% satisfaction.

All modern air conditioning systems, even small window package units, are equipped with internal air filters. These are generally of a lightweight gauzy material, and must be replaced or washed as conditions warrant. For example, a building in a high dust environment, or a home with furry pets, will need to have the filters changed more often than buildings without these dirt loads. Failure to replace these filters as needed will contribute to a lower heat exchange rate, resulting in wasted energy, shortened equipment life, and higher energy bills; low air flow can result in iced-over evaporator coils, which can completely stop air flow. Additionally, very dirty or plugged filters can cause overheating during a heating cycle, and can result in damage to the system or even fire.


This may apply to a system using fresh air for cooling the space or a water cooled or glycol cooled system with an additional coil that provides chilled water cooling when the outdoor ambient is cold; thereby reducing or eliminating compressor operation. These systems may provide free cooling for up to 80% of their operating life, particularly when operating in Northerly climates. See our Free Cooling page for more information.
We are service professionals! As licensed contractors and specialists in the field of heating and air conditioning, we have the tools, the equipment, and the experience to keep your equipment running smoothly all year long. If it is emergency service that you need we are available to assist you! To help reduce service emergencies, we offer service agreements to keep your comfort system running at peak performance.

An important component of natural ventilation is air change rate or air changes per hour: the hourly rate of ventilation divided by the volume of the space. For example, six air changes per hour means an amount of new air, equal to the volume of the space, is added every ten minutes. For human comfort, a minimum of four air changes per hour is typical, though warehouses might have only two. Too high of an air change rate may be uncomfortable, akin to a wind tunnel which have thousands of changes per hour. The highest air change rates are for crowded spaces, bars, night clubs, commercial kitchens at around 30 to 50 air changes per hour.[17]


Heating, Ventilating, and Air Conditioning (HVAC) equipment perform heating and/or cooling for residential, commercial or industrial buildings. The HVAC system may also be responsible for providing fresh outdoor air to dilute interior airborne contaminants such as odors from occupants, volatile organic compounds (VOC’s) emitted from interior furnishings, chemicals used for cleaning, etc. A properly designed system will provide a comfortable indoor environment year round when properly maintained.
We install heating equipment from Lennox and can repair all major brands, including Carrier, Trane, York, Bryant, Rheem, and many more. We proudly offer same day service and next day installations. Dealing with a heating emergency? We've got you covered! Our team is prepared to assist you 24 hours a day, 7 days a week to ensure that your home remains comfortable and safe for you and your family members.
At Donelson Air Service Experts Heating & Air Conditioning, we understand heating and air conditioning, which is why we back up our work with our 100% Satisfaction Guarantee*. Not only does it demonstrate our confidence that you’ll be happy with the furnace repair we have completed, it holds us to a higher standard, ensuring that we continue to provide you with superior service without fail. When it’s time to handle any heating and cooling question or issue you have, know that you can trust the experts at Donelson Air Service Experts regardless of what the Nashville weather brings.
HVAC System Quality Installation Contractor Checklist -- This checklist identifies all of the steps the contractor has taken for the Energy Star Certification and identifies what work the contractor has done. If the system is later modified, this checklist can help identify what was done to proper Energy Star specifications and what was added later that may not meet the requirements.
Deljo Heating & Cooling is also a Mitsubishi Diamond Dealer, guaranteeing a superior skill set, dedicated customer service and sophisticated solutions to the most challenging home temperature concerns. Our technicians participate in extensive training and education at every level of service, from new product sales to continued customer care, at a Mitsubishi Electric-approved training center. Through intensive training and years of firsthand experience, our HVAC....
SEER is related to the coefficient of performance (COP) commonly used in thermodynamics and also to the Energy Efficiency Ratio (EER). The EER is the efficiency rating for the equipment at a particular pair of external and internal temperatures, while SEER is calculated over a whole range of external temperatures (i.e., the temperature distribution for the geographical location of the SEER test). SEER is unusual in that it is composed of an Imperial unit divided by an SI unit. The COP is a ratio with the same metric units of energy (joules) in both the numerator and denominator. They cancel out, leaving a dimensionless quantity. Formulas for the approximate conversion between SEER and EER or COP are available.[34]
Before selecting the installation location of air conditioner, several main factors need to be considered. First of all, the direction of air flow from the indoor units should not fall on the place of rest or work area. Secondly, there should not be any obstacles on the way of the airflow that might prevent it from covering the space of the premises as much as possible. The outdoor unit must also be located in an open space, otherwise the heat from the house will not be effectively discharged outside and the productivity of the entire system will drop sharply. It is highly advisable to install the air conditioner units in easily accessible places, for further maintenance during operation.

A number of other variables can influence your decision on whether to repair or replace your furnace, as well. In addition to cost and brand, consider the expected lifetime of your furnace. If it is more than 15 years old, it might make more sense to invest in a new unit even if it costs more than simply repairing the current problem. Long-term costs also play into the equation. For example, your new furnace may be more energy efficient than the current unit. Even though you will pay more for the actual installation, you might be able to make back your investment through lower energy bills. To make your decision, consult with a reliable professional on what to do. In inspecting your furnace, they will be able to make an informed recommendation that looks not just to the next year, but years into the future. That way, you can make the best possible decision for your home and budget long-term.


Heil HVAC is another one of the best air conditioner brands that doesn’t get as much love as they should. This AC brand’s tech allows different heating and cooling components  send information and synchronize performance, becoming more energy efficient and reliable overall. Heil AC products can achieve up to a 97% efficiency rating and SEER figures of 19. They also come with comprehensive 10 year warranties.

A number of other variables can influence your decision on whether to repair or replace your furnace, as well. In addition to cost and brand, consider the expected lifetime of your furnace. If it is more than 15 years old, it might make more sense to invest in a new unit even if it costs more than simply repairing the current problem. Long-term costs also play into the equation. For example, your new furnace may be more energy efficient than the current unit. Even though you will pay more for the actual installation, you might be able to make back your investment through lower energy bills. To make your decision, consult with a reliable professional on what to do. In inspecting your furnace, they will be able to make an informed recommendation that looks not just to the next year, but years into the future. That way, you can make the best possible decision for your home and budget long-term.


Start with your utility company; they can help a great deal. Comparing previous bills isn't always a good measure, as the weather is never exactly the same month to month. Instead, if you take your energy bill and divide it by the square footage of livable space in your home, don't count areas like unfinished garages or basements -- you can calculate how much you are spending to heat or cool each square foot of your home. Your energy provider can tell you what the average cost per square foot is in your region for that same period of time so you can compare apples to apples.
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