The use of CFC as a refrigerant was once common, including the refrigerants R-11 and R-12 (sold under the brand name Freon-12). Freon refrigerants were commonly used during the 20th century in air conditioners due to their superior stability and safety properties. When they are released accidentally or deliberately, these chlorine-bearing refrigerants eventually reach the upper atmosphere.[61] Once the refrigerant reaches the stratosphere, UV radiation from the Sun homolytically cleaves the chlorine-carbon bond, yielding a chlorine radical. These chlorine radicals catalyze the breakdown of ozone into diatomic oxygen, depleting the ozone layer that shields the Earth's surface from strong UV radiation. Each chlorine radical remains active as a catalyst until it binds with another radical, forming a stable molecule and quenching the chain reaction.
The first air conditioners and refrigerators employed toxic or flammable gases, such as ammonia, methyl chloride, or propane, that could result in fatal accidents when they leaked. Thomas Midgley, Jr. created the first non-flammable, non-toxic chlorofluorocarbon gas, Freon, in 1928. The name is a trademark name owned by DuPont for any chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC), or hydrofluorocarbon (HFC) refrigerant. The refrigerant names include a number indicating the molecular composition (e.g., R-11, R-12, R-22, R-134A). The blend most used in direct-expansion home and building comfort cooling is an HCFC known as chlorodifluoromethane (R-22).
Your furnace's flame sensor is essentially a safety mechanism. As a thin metallic rod in front of the flame inside the unit, it's sole purpose is to confirm that your gas valves only open when a flame actually exists to burn that gas. When the flame sensor stop working, on the other hand, gas leaks can occur. To repair your furnace's flame sensor, expect to spend between $80 and $250. Even a full replacement of this part typically does not go above that range.

Your HVAC professional can also help you verify that your system is properly matched by providing you with an AHRI Certificate of Certified Product Performance upon request. The certificate verifies that the outdoor unit (condenser) and the indoor unit (evaporator) combination has been certified as a matched system by the Air Conditioning, Heating and Refrigeration Institute (AHRI). For higher efficiency systems, this certification may help you obtain a rebate from your utility or local municipality if you have to replace your unit in whole or in part. Not all areas offer a rebate, but your technician will likely be able to provide information about the certification process. Fees for performing this certification vary, but generally are relatively inexpensive.
Any concern with your cooling system, however minor, is worth checking out.  NATE-certified technicians can quickly identify the problem and prevent more extensive and costly damage.  Catching defects quickly is the key to cost-effective repairs.  Elevated operational noise such as grinding, screeching, or wheezing is more than aggravating.  Think of those sounds as warning bells.  They’re an indication of component failure.  Listen to what they’re telling you and call for professional assistance.  Worn or misaligned belts are easily repaired.  Strange smells from contaminants such as mold or mildew are best handled before allergens enter breathing air, diminish airflow, and block the coil.  Temperature swings, unstable humidity, or extended run times are all signs of bigger problems on the way.  Call Ferran Services at 407-422-3551 (Orlando) or 386-322-6168 (Volusia), and our licensed technicians will perform a complete system check, ensuring safe, efficient and reliable operation.
You can usually slip the belt on the motor’s (smaller) pulley first and then start it on the blower pulley. Rotate the blower pulley by hand, holding the belt in place but keeping your fingers from getting caught between the belt and the pulley. The belt should slip right into place. If it seems to be too tight or difficult to set in place, it may be necessary to adjust the motor mount to provide more slack.
Mr. Plumber provides fast, expert plumbing service to Smyrna, GA and is here for you with 24 hour emergency plumbing service. Our licensed and certified plumbers can tackle all your plumbing jobs including sink & faucet repair, toilet repair & replacement, water line repair & replacement, drain cleaning, bathtubs & shower installation and repair, water heater installation, sewer repair, backflow prevention and more. Our professional plumbers will respect your time, home and business. You approve the price before we perform our plumbing work and your satisfaction is guaranteed! Give us a call today for:

Although HVAC is executed in individual buildings or other enclosed spaces (like NORAD's underground headquarters), the equipment involved is in some cases an extension of a larger district heating (DH) or district cooling (DC) network, or a combined DHC network. In such cases, the operating and maintenance aspects are simplified and metering becomes necessary to bill for the energy that is consumed, and in some cases energy that is returned to the larger system. For example, at a given time one building may be utilizing chilled water for air conditioning and the warm water it returns may be used in another building for heating, or for the overall heating-portion of the DHC network (likely with energy added to boost the temperature).[4][5][6]

We relocate frequently and one of the biggest hassles of relocating to new areas is finding reputable companies that send qualified technicians to perform work when you need it, whether for annual preventative maintenance or during a house emergency. We’ve been through the process several times and always dread researching and trying new companies. This was our first HVAC call here in northern Virginia. We are in new construction and chose not to use the builder’s sub-contractor for a technician call but looked through Carrier’s website for a local business. Jeremy Garner with HVAC Unlimited responded to our service request the morning following our call. I shadowed him performing work and he was patient while I peppered him with questions. He helped expand my HVAC knowledge in order to be a better property owner of our systems. He performed the work we thought was necessary, in a timely and professional manner, and gave us options for future annual maintenance. HVAC Unlimited is definitely on our list of go-to contractors.
Central home air conditioner service systems consist of two major components: a condensing unit that sits outside your house, and the evaporator coil (often referred to as an A-coil) that sits in the plenum of your furnace or air handler. The refrigerant in the A-coil picks up the heat from your home and moves it to the outdoor condensing unit. The condensing unit fan blows outside air through the condensing coil to remove the heat. The condensing unit houses the three parts replaceable by a DIYer: the contactor, the start/run capacitor(s) and the condenser fan motor. The condensing unit also houses the compressor, but only a pro can replace that. The A-coil has no parts that can be serviced by a DIYer.
"Very impressed. Returned call within 24 hours. They came out the same day I spoke with them and made the repair within 25 minutes. Very low service call fee. I had another repair service out two weeks earlier and after 3 service calls and the central air still not fixed and temperatures in the high 90's, it was such a relief to have a company identify the problem, have the necessary part with them and fix the problem."
If you have forced-air cooling but there’s still a room that’s hotter than all the rest, a duct or vent booster fan can increase the flow of cool air into that room. Two types of booster fans are available. An in-line duct booster fan (shown) fits inside the duct of the room you’re trying to cool. You mount the fan near the outlet and it automatically kicks on when your cooling system runs.
The Environmental Protection Agency (EPA) requires that all technicians who open a system containing a controlled refrigerant be certified to do so. There are four levels of certification, one of which is a “universal” certification to allow the HVAC technician to work on any type of equipment containing refrigerant. Your HVAC technician should be certified as “Level II Certified” at a minimum or, preferably, “Universal Certification” to work on your central air conditioner. Obtaining this certification information from your professional HVAC technician may be required in the event you are working with a realtor to sell your home. Costs for certification average $40 to $240.
We want to compliment your fine sales and installation team. They are outstanding. Carlos, your sales rep., was highly informative. We reviewed our needs and we ultimately chose the Trane XV-18 variable speed system. Carlos did not try to up sell us with things that we did not need but he did help us choose the correct upgraded filter and UV light that we wanted. We told Carlos that our research indicated that the quality of the installation of the unit was at least as important as the unit itself, and Carlos agreed. Carlos pointed out that new proper sized duct work and copper wiring would be required for a correct installation, and that we needed to add two more returns. We asked if more returns were needed and Carlos said that would not be cost effective. That was great to hear. Carlos assured us that the installation team of Willie and Gary, both lead installers, would be used. They were both superb. They came on time and worked for 12 and 1/2 hours. It was a 93 degree day so the heat in the attic was intense. We kept telling them to take a break but they continued to work up there in what must have been 130+ temperatures. They were amazing! They were neat and cleaned up any mess they made. They patiently answered all of our many questions and gave us helpful tips. They were truly professional in all respects. We also note that Stacy, Angie and Karen of your office staff were each courteous, accommodating and efficient. They helped things to go smoothly. Carlos, Gary, Stacy, Angie, Willie and Karen are each great assets to your company. We would be comfortable recommending that team of people to anyone! Ken and Kathy Luban
Please give us a call today at 1-800-948-MIKE (6453) for first-class air conditioning service and repairs in the Springfield, VA, Rockville, Silver Spring, MD & Washington D.C. metro area. We’re open seven days a week and provide 24/7 emergency service. For those who want to ensure that their AC unit is in working order before the summer season begins – or at any other time – we proudly offer a Heating & Cooling precision tune up to troubleshoot any potential AC problems. Upon completion of the AC inspection, we will provide you with a comprehensive written report regarding your Air Conditioning and Heating system’s status and make any recommendations necessary to improve your comfort level and head off any problems before they arise.
The manufacture and use of CFCs has been banned or severely restricted due to concerns about ozone depletion (see also Montreal Protocol).[64][65] In light of these environmental concerns, beginning on November 14, 1994, the U.S. Environmental Protection Agency has restricted the sale, possession and use of refrigerant to only licensed technicians, per rules under sections 608 and 609 of the Clean Air Act.[66]
An air conditioning system, or a standalone air conditioner, provides cooling and humidity control for all or part of a building. Air conditioned buildings often have sealed windows, because open windows would work against the system intended to maintain constant indoor air conditions. Outside, fresh air is generally drawn into the system by a vent into the indoor heat exchanger section, creating positive air pressure. The percentage of return air made up of fresh air can usually be manipulated by adjusting the opening of this vent. Typical fresh air intake is about 10%.
Given the broad price ranges above, it's easy to recognize that the cost of your furnace repair varies drastically based on which parts need attention. As a result, it makes sense to gain a better understanding of the parts that heat your home, and how much they cost to repair. Repairing or replacing your furnace’s blower motor can cost you anywhere between $150 and $450, depending on the extent of the damage. Heat exchanger repair costs can vary greatly, from as little as $100 for a simple fix to as much as $1,200 for a full replacement. Repairing a furnace igniter will only cost you $300 at most, while flame sensor repairs generally fall between $80 to $250. The average cost to repair your Thermostat will range from $108 to $282.
In 1758, Benjamin Franklin and John Hadley, a chemistry professor at Cambridge University, conducted an experiment to explore the principle of evaporation as a means to rapidly cool an object. Franklin and Hadley confirmed that evaporation of highly volatile liquids (such as alcohol and ether) could be used to drive down the temperature of an object past the freezing point of water. They conducted their experiment with the bulb of a mercury thermometer as their object and with a bellows used to speed up the evaporation. They lowered the temperature of the thermometer bulb down to −14 °C (7 °F) while the ambient temperature was 18 °C (64 °F). Franklin noted that, soon after they passed the freezing point of water 0 °C (32 °F), a thin film of ice formed on the surface of the thermometer's bulb and that the ice mass was about 6 mm (1⁄4 in) thick when they stopped the experiment upon reaching −14 °C (7 °F). Franklin concluded: "From this experiment one may see the possibility of freezing a man to death on a warm summer's day."[9]
×