Just as a doctor needs diagnostic tools for the human body’s electrical and hydraulic systems, the HVAC technician requires tools to “look” inside air conditioning and refrigeration circuits. When large HVAC commercial systems are down, the technician feels the pressure to get systems back online. It takes a well-trained professional to properly repair big commercial refrigeration and air conditioning installations. Having high quality diagnostic equipment is the technician’s best friend for getting things fixed and working faster. Here are some examples of todays most advanced tools for HVAC troubleshooting.
Its 95 degrees on a hot, humid day. A service repairman, working on your HVAC, opens the door to your vented crawlspace. He observes ductwork dripping with water, mold on floor joist, and termite tunnels on the crawlspace walls. He services your air conditioner and recommends you call an exterminator. Why are you having all these issues in your crawlspace? Could it be that the naturally vented crawlspace doesn’t work anymore? Some people would say, it never worked. Why is this?
When we see the acronym HVAC, most only think of heating and air conditioning. But the V is for ventilation, an important role when considering the air quality in buildings. Indoor air quality is achieved through ventilating and filtering air in a space. The International Mechanical Code’s definition of ventilation is “The natural or mechanical process of supplying conditioned or unconditioned air to, or removing such air from, a space.” When we supply fresh air to spaces and remove stale air, we improve the breathing air quality for the occupants. When air is “conditioned”, it means several things that include removing or adding heat, cleaning the air, removing moisture, and replacing air.
In the recent past, a mechanical contractor could install very inefficient appliances and equipment with no thought to energy costs. Energy rates were cheap; therefore, mechanical codes did not address energy usage. Mechanical code emphasis was on installation integrity, clearance to combustibles, and service space requirements. The installed equipment was very heavy and overbuilt. That all changed in the late 20th century due to several economic and environmental factors. These factors created a new buzzword: energy conservation.
What if a refrigeration system could exist without a mechanical compressor, oil, or the typical blended refrigerant? A totally new design that required much less electricity to operate? Components of the system consist of an inert gas and large pressure vessels connected by pipes. This mechanism would be based on thermoacoustic principles that had very few moving parts. Considering the environmental issues faced today, wouldn’t it be an amazing achievement?
The combining of fuel, air and an ignition source creates combustion. This combustion process is utilized in furnaces and water heaters to heat air or water. Byproducts of combustion are carbon dioxide, water, occasionally carbon monoxide and other gases.
According to industry experts there are over 100,000 HVAC contractors currently doing business in the U.S. However, statistics show that 50% of small business startups fail within the first year and 95% fail within five years. Therefore, the 100,000 plus contractors successfully doing business have figured a thing or two out. Let’s look at some standard business practices of these HVAC companies that keep them profitable and out of the failure statistics.
The mini-split heating and cooling system was an idea that evolved from the basic window air conditioner. Window units are simple installations that offer room by room temperature control if enough are installed. However, window units are noisy. To minimize noise, the window unit compressor was moved to a remote location using refrigerant lines to connect to the inside fan-coil. As a result, the mini-split system was born. This product first saw mass appeal in Asian markets. Today these systems are found throughout the world and has become a big player in the domestic HVAC market.
When homeowners receive quotes from HVAC contractors, they typically are given two duct replacement options, sheet metal or fiberglass duct board. There is a third option, phenolic duct, that is made of plastic foam with a foil liner on the inside and exterior. It hasn’t been on the market long enough to weigh in on its merits and shortcomings and will not be included in this comparison. Homeowners usually go for the product their HVAC contractor recommends; however, all systems have their strengths and weaknesses. Here are the advantages and disadvantages of two of these materials when installed in the typical residence.
Georgia Air Conditioned Contractor licenses have an upcoming expiration date of 11/30/2019. Licensees must renew their license before the expiration date in order to keep it valid.
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