The main purpose of your furnace filter is to ensure that none of the additional materials your fans pull back into the unit - such as hair and dust - actually damage the furnace or its parts. In the process, it also improves air quality in your home. Some annual inspections will include changing and cleaning this part of the unit. That said, you can also clean or change your furnace filteryourself. Costs for new filters range based on brand, but tend to be around $30.

The Chartered Institution of Building Services Engineers is a body that covers the essential Service (systems architecture) that allow buildings to operate. It includes the electrotechnical, heating, ventilating, air conditioning, refrigeration and plumbing industries. To train as a building services engineer, the academic requirements are GCSEs (A-C) / Standard Grades (1-3) in Maths and Science, which are important in measurements, planning and theory. Employers will often want a degree in a branch of engineering, such as building environment engineering, electrical engineering or mechanical engineering. To become a full member of CIBSE, and so also to be registered by the Engineering Council UK as a chartered engineer, engineers must also attain an Honours Degree and a master's degree in a relevant engineering subject.
The liquid refrigerant is returned to another heat exchanger where it is allowed to evaporate, hence the heat exchanger is often called an evaporating coil or evaporator. As the liquid refrigerant evaporates it absorbs energy (heat) from the inside air, returns to the compressor, and repeats the cycle. In the process, heat is absorbed from indoors and transferred outdoors, resulting in cooling of the building.
Absorption refrigerator Air barrier Air conditioning Antifreeze Automobile air conditioning Autonomous building Building insulation materials Central heating Central solar heating Chilled beam Chilled water Constant air volume (CAV) Coolant Dedicated outdoor air system (DOAS) Deep water source cooling Demand-controlled ventilation (DCV) Displacement ventilation District cooling District heating Electric heating Energy recovery ventilation (ERV) Firestop Forced-air Forced-air gas Free cooling Heat recovery ventilation (HRV) Hybrid heat Hydronics HVAC Ice storage air conditioning Kitchen ventilation Mixed-mode ventilation Microgeneration Natural ventilation Passive cooling Passive house Radiant heating and cooling system Radiant cooling Radiant heating Radon mitigation Refrigeration Renewable heat Room air distribution Solar air heat Solar combisystem Solar cooling Solar heating Thermal insulation Underfloor air distribution Underfloor heating Vapor barrier Vapor-compression refrigeration (VCRS) Variable air volume (VAV) Variable refrigerant flow (VRF) Ventilation
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.
When your furnace isn’t regularly serviced it can operate less efficiently. This increases your energy bills and also prevents your furnace from keeping your home as warm as you like. Keep your furnace properly maintained with regular service. The national average furnace service cost is between $60 and $80. Companies may offer tuneup specials that cover all the necessary testing, tightening, measuring and cleaning to keep your equipment running at top efficiency. If you have a newer system, furnace service costs may be covered by your warranty. Outside of warranty, a basic tuneup might start at $58 and a more advanced maintenance cleaning could be over $120. Here are some signs your furnace may need service:
Free cooling systems can have very high efficiencies, and are sometimes combined with seasonal thermal energy storage so that the cold of winter can be used for summer air conditioning. Common storage mediums are deep aquifers or a natural underground rock mass accessed via a cluster of small-diameter, heat-exchanger-equipped boreholes. Some systems with small storages are hybrids, using free cooling early in the cooling season, and later employing a heat pump to chill the circulation coming from the storage. The heat pump is added-in because the storage acts as a heat sink when the system is in cooling (as opposed to charging) mode, causing the temperature to gradually increase during the cooling season.
Dichlorodifluoromethane (R-12) was the most common blend used in automobiles in the U.S. until 1994, when most designs changed to R-134A due to the ozone-depleting potential of R-12. R-11 and R-12 are no longer manufactured in the U.S. for this type of application, so the only source for air-conditioning repair purposes is the cleaned and purified gas recovered from other air conditioner systems. Several non-ozone-depleting refrigerants have been developed as alternatives, including R-410A. It was first commercially used by Carrier Corp. under the brand name Puron.[citation needed]
American design standards are legislated in the Uniform Mechanical Code or International Mechanical Code. In certain states, counties, or cities, either of these codes may be adopted and amended via various legislative processes. These codes are updated and published by the International Association of Plumbing and Mechanical Officials (IAPMO) or the International Code Council (ICC) respectively, on a 3-year code development cycle. Typically, local building permit departments are charged with enforcement of these standards on private and certain public properties.
Bonney’s NATE certified technicians will troubleshoot and repair your furnace for safe and reliable operation. Our technicians use state of the art tools including video inspection cameras and exhaust gas analyzers to perform thorough, comprehensive diagnostics when equipment is broken. Furthermore, we arrive in a “warehouse on wheels” stocked with many parts to get your furnace repaired as quickly as possible.  For an unexpected heater repair Bonney offers financing to make your comfort affordable.
If your home is not heated using forced air, chances are a boiler will make sure you stay warm during cold nights. A hot water system delivers hot water through a network of pipes that run to every room in your house. The heating effect gets maximized through radiators. The most common issues with hot water heating tend to be not be major, but small problems that add up over time. Mineral deposits within the water tank, a pilot light malfunction, or an issue with a radiator itself can require professional repair. On average, you will pay between $183 and $582 for these problems. The exact amount will depend on the exact problem, as described in our boiler repair cost guide.
Consequently, this water must exit the air handler—typically through plastic pipe or a drain tube. That drain tube goes directly outside, often terminating near the compressor, or to a floor drain or to a small electric “condensate pump” located by the air handler. Where a condensate pump is used, it connects to a 1/2-inch vinyl or rubber tube that exits outdoors or to a drain.

Our team of fully licensed and insured technicians each draw from between ten and thirty years of industry experience and share our unwavering dedication to customer service.  Entirely NATE-certified, our installation and service department has completed rigorous testing, and are exceptionally qualified to handle even the most complex HVAC challenges.  NATE (North American Technician Excellence) is the only nationwide certification program that is supported by the entire industry, and of all third-party certifications, has the lowest pass rate.

The cost to replace your gas furnace will vary based on the type and size of furnace you select, labor and installation costs, and any repairs your HVAC system may need. Nationally, average HVAC prices for a heating specialist range between $1,800 and $2,500. It’s important to select the right size gas furnace for your heating needs. A furnace that’s too small won’t heat your house properly, while a furnace that’s too large will run inefficiently, cycling on and off and likely breaking down sooner. HVAC specialists calculate your exact heat needs by measuring your home and incorporating variables such as the regional climate and your home’s level of insulation. Retail pricing for gas furnaces can range from $650 up to $3,000 and more. The higher the AFUE (annual fuel utilization efficiency) rating of the furnace, the more efficient it is at turning fuel into heat and the lower your carbon footprint and utility bill will be. HVAC installation costs are often based on an hourly rate and can range from under $50 to over $100 per hour, depending on the company and the furnace being installed. Higher-end furnaces cost more to install because they require added labor and expertise. For a typical installation, it might take two HVAC installation pros one day or less to remove your old furnace and replace it with a new one.


A heat pump is an air conditioner in which the refrigeration cycle can be reversed, producing heating instead of cooling in the indoor environment. They are also commonly referred to as a "reverse cycle air conditioner". The heat pump is significantly more energy efficient than electric resistance heating. Some homeowners elect to have a heat pump system installed as a feature of a central air conditioner. When the heat pump is in heating mode, the indoor evaporator coil switches roles and becomes the condenser coil, producing heat. The outdoor condenser unit also switches roles to serve as the evaporator, and discharges cold air (colder than the ambient outdoor air).
The summers here in Alexandria can range from almost pleasant to downright brutal. And you know as well as we do that it’s those latter days when your central AC or heat pump will decide to go down! But you don’t have to seek solace at the Waterfront or over at Cameron Run Regional Park. The secret to restoring your comfort lies with the certified specialists at HVAC & Plumbing Unlimited!
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]
Furnace breakdowns, no cooling when outside temperatures are soaring – heating and cooling repairs often catch us unexpectedly, making HVAC repair costs quite a surprise. Many homeowners worry when calling the HVAC repair contractor because of unexpected costs – your heating and cooling contractor won’t be able to give you a price for the repairs needed until he or she inspects the system to find the source of the problem.

The cost to replace your gas furnace will vary based on the type and size of furnace you select, labor and installation costs, and any repairs your HVAC system may need. Nationally, average HVAC prices for a heating specialist range between $1,800 and $2,500. It’s important to select the right size gas furnace for your heating needs. A furnace that’s too small won’t heat your house properly, while a furnace that’s too large will run inefficiently, cycling on and off and likely breaking down sooner. HVAC specialists calculate your exact heat needs by measuring your home and incorporating variables such as the regional climate and your home’s level of insulation. Retail pricing for gas furnaces can range from $650 up to $3,000 and more. The higher the AFUE (annual fuel utilization efficiency) rating of the furnace, the more efficient it is at turning fuel into heat and the lower your carbon footprint and utility bill will be. HVAC installation costs are often based on an hourly rate and can range from under $50 to over $100 per hour, depending on the company and the furnace being installed. Higher-end furnaces cost more to install because they require added labor and expertise. For a typical installation, it might take two HVAC installation pros one day or less to remove your old furnace and replace it with a new one.
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]
If you’re looking to maintain, replace, or repair your home or business’s air conditioning system, “Make the Precision Decision”™ and give us a call. We are available 24/7 for all your emergency service needs. Our service area includes Litchfield Park, Mesa, Avondale, Peoria, Phoenix, Chandler, Scottsdale, Sun Lakes, Gilbert, Surprise, Glendale, Tempe, Goodyear and surrounding areas.

The condensed, pressurized, and still usually somewhat hot liquid refrigerant is next routed through an expansion valve (often nothing more than a pinhole in the system's copper tubing) where it undergoes an abrupt reduction in pressure. That pressure reduction results in flash evaporation of a part of the liquid refrigerant, greatly lowering its temperature. The cold refrigerant is then routed through the evaporator. A fan blows the interior warm air (which is to be cooled) across the evaporator, causing the liquid part of the cold refrigerant mixture to evaporate as well, further lowering the temperature. The warm air is therefore cooled and is pumped by an exhaust fan/ blower into the room. To complete the refrigeration cycle, the refrigerant vapor is routed back into the compressor. In order for the process to have any efficiency, the cooling/evaporative portion of the system must be separated by some kind of physical barrier from the heating/condensing portion, and each portion must have its own fan to circulate its own "kind" of air (either the hot air or the cool air).
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