Mayne Mechanical

11/23/2022

Happy Thanksgiving to all of our customers, employees and friends.

03/24/2022

Commercial sheet metal installers and helpers.

03/24/2022

Commercial HVAC service Technician
Experience a must.

03/24/2022

Commercial HVAC Service Technician
Mayne Mechanical - Baltimore, MD
HVAC Service Technicians
Looking for a service tech to service commercial HVAC equipment consisting of packaged rooftop equipment, VAV, VRF, heat pumps, cooling towers, pumps, control systems.
Experience - 5 Yrs W/Journeyman & CFC certification. Someone able to work independently and communicate with customers.
Benefits include - Paid vacation, personal leave, health insurance, life insurance, disability, company truck and tablet.
Job Type: Full-time
Job Type: Full-time

03/02/2021

Commercial HVAC service Technician
Experience a must.

02/24/2021

UV Air Purification

With COVID-19 being part of our lives. We are happy to install UV light systems to keep viruses and germs at bay.

02/24/2021

Commercial sheet metal installers and helpers.

02/24/2021

Commercial HVAC Service Technician
Mayne Mechanical - Baltimore, MD
HVAC Service Technicians
Looking for a service tech to service commercial HVAC equipment consisting of packaged rooftop equipment, VAV, VRF, heat pumps, cooling towers, pumps, control systems.
Experience - 5 Yrs W/Journeyman & CFC certification. Someone able to work independently and communicate with customers.
Benefits include - Paid vacation, personal leave, health insurance, life insurance, disability, company truck and tablet.
Job Type: Full-time
Job Type: Full-time

03/16/2017

Something to think about

10/19/2016

Mayne Mechanical has some new vans to show off.

12/05/2014

Hair club for men in Annapolis MD. It's not just a job. It's a job well done.

12/04/2014

Morty's Deli at Maryland Live.

06/27/2014

BuilderGuru | National General Contractor – Trusted Builders – Derwood Bible Church

Derwood Bible church Another job well done by Mayne Mechanical.

General Construction Contractors Building New Construction Projects & Commercial Construction Jobs. BuilderGuru & Gardiner & Gardiner Build Your Trust

06/10/2014

Crane lift

05/20/2014

History of Refrigeration
A Brief History of Refrigeration
J. Caldwell, 1943-2008

Not long after Man began to use fire to cook and to keep himself warm, he found ways to cool his food and himself. Some believe that the invention of beer provided the impetus to develop refrigeration. We can understand the urgency, but the truth is lost in the mists of time.

In northern climes, early man found he could keep food longer if he buried it in the cool earth or stored it in caves. He probably found edible dead game encased in ice, and began to harvest and store ice as a means of refrigeration. But what about hot climates? How did man try to cope with the blazing heat of the desert? The remains of pottery found all over the world show that unglazed clay containers were widely used for water receptacles. Being porous, the unglazed pottery allows water to pe*****te the pot and ev***rate on the outside surface, cooling the pot and its contents. The drier the climate, the colder the result. There is an indication that the ancient Egyptians invented comfort cooling, using slaves to fan air through suspended damp fabric to cool the royal personages on hot days. This ev***rative air cooling exists today in the “swamp coolers” that we see sprouting on roofs in the southwest United States. Fountains were built for more than aesthetic reasons: the splashing water partially ev***rates, cooling the remaining water and the surrounding air.

A particularly interesting form of cooling is radiation to the sky. At night, the earth radiates heat energy into space. In parts of the middle east, due to the dry, clear air, ice will form on the surface of pans of water exposed to the night sky, even though the surrounding air is above freezing. This process was actually used in ancient times to produce ice for cooling drinks. In the 1500's it was discovered that certain metal salts such as sodium or potassium nitrate, when added to water, produce a hypothermic mixture, cold enough to form ice in pure water. This process was used in France before 1700 to make iced and frozen drinks by suspending a container of juice or pure water in a bath of the cold salt mixture. So maybe the search for a cold drink really was the impetus for refrigeration.

In 1748 a professor at the University of Glasgow demonstrated the formation of ice on the surface of a flask containing ev***rating ether under a partial vacuum. This would have been the birth of the compression-ev***ration cycle system most common today, if he had captured, compressed, condensed and re-ev***rated the ether v***r. Over the next century various methods of cooling were devised, primarily to cool foodstuffs. The first U.S. patent for mechanical refrigeration was issued in 1851 to a Florida doctor who developed an air-cycle system to build ice, which was then used to cool a yellow fever ward. This method is used today for in-flight air conditioning on our commercial jet passenger aircraft, and uses air as the refrigerant, compressing and expanding it to cool it. By the time of our civil war, mechanical refrigeration systems using the compression-ev***ration or the air-cycle were being commercially used to make ice, which was then used to cool meat, milk and beer. The first ammonia compression system was developed in France in 1859, and various refrigerants were used with varying success, including water, carbon dioxide and sulphur dioxide. Ammonia became the primary refrigerant of choice, and is still in use today. “Freon” and other halogenated fluorocarbon refrigerants were developed after World War I to replace the toxic ammonia. Now the search is on for efficient refrigerants that do not contain the chlorine compounds that we believe are destructive to the ozone layer of our atmosphere.

Many early systems were used to manufacture bulk ice, for use in food transportation. These were rated according to their daily ice production, expressed in “tons”. Thus, a one-ton system could produce 2000 lb. of ice in 24-hours (12,000 Btu per hour). This arcane unit of measure is still in use today in the U.S. for refrigeration and air-conditioning systems. High-tech forms of refrigeration are being developed, including thermo-electric and acoustic, as we find more and better ways to make things cold.

This article is published in Loving Memory of our friend and Colleague, Mr John Caldwell
Some historical details in this article are taken from A History of Refrigeration by Roger Thevenot, published by The International Institute of Refrigeration, Paris, 1979, English translation by J. C. Fidler.

05/20/2014

Orthopedic Associates in Catonsville Maryland

05/20/2014

Merkle building in Columbia,MD

05/20/2014

Mayne Mechanical | Heating, Ventilating, & Air Conditioning, | Eldersburg, Maryland

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Our standard scope of services includes the following CSI Master Format™ code(s).We typically self-perform all materials and installations, unless otherwise indicated below.