When was forced air heating invented

We are living in some amazing times. Information has exploded over the past century, especially during the past couple of decades. And the HVAC industry has seen some incredible advances during that same time. But have you ever wondered how we arrived at this point? How did our ancestors keep warm throughout history?

Human survival has always been dependent on staying warm during the coldest times of the year. For most of human history, our ancestors stayed warm through open fire or wood-burning fireplaces. Just a short distance away from these fires, you would get cold again, quickly.

In 15 AD, the Romans described a type of radiator for creating space heat called the hypocaust. But the modern heating radiator was invented around by Franz San Galli. Petersburg Russia. Temples were heated by heat that was generated by fire and circulated by flues. Ancient romans used a similar heating technique that consisted of furnaces used to heat air through the walls and under floors that eventually heated an entire room.

In the early s, Strutt teamed up with engineer Charles Sylvester to design a heating system for a hospital that cleaned the air along with heating the building.

Scottish inventor James Watt built the first working central boiler system in his home. His invention involved high-pressure steam that was distributed through pipes. Other attempts were made by engineers in several other countries but their concepts were mostly used for heating greenhouses.

The radiator — an important piece of modern central heating — was invented in the late s by Russian inventor Franz San Galli and adopted by most of Europe and the United States. In addition to providing hot water, radiators were able to spread heat.

Not all rooms in homes were able to be heated following World War II because of the large amount of equipment. Electric heating was also introduced in the late s, paving the way for a much more comfortable and less expensive way of heating. To schedule a furnace repair , contact our friendly team or call AD : Cistercian monks in Christian Europe revive central heating using river diversion and wood-burning furnaces. The first chimneys also appear at this time.

AD : Masonry stoves appear and become common by the s, which is also when chimneys become more refined. AD : Louis Savot of France invents the circulating fireplace with the creation of a raised grate that promoted airflow. Early s : Individuals in England use combustion air from an outside duct. AD : Benjamin Franklin invents the Franklin stove, which was more efficient than other stoves used at the time.

Late s : James Watt of Scotland develops the first working steam-based heating system for his home using a central boiler and a system of pipes. Nelson Bundy invented the first popular cast iron radiator in By the s, cast iron sectional radiators became very popular. Competition between manufacturers of boilers and radiators was intense. As in the furnace business, bankruptcies and consolidations were frequent.

The late 19th century saw the rise of the Business Trust, and the heating industry was quick to use this business form to improve the competitive situation. The most successful such trust was the American Radiator Company, which consolidated a number of the leading boiler and radiator manufacturers in The company was the Microsoft of its time.

Its success in capturing most of the radiator business is evident when surveying buildings with old radiators — American Radiator made most of them. The company exists today as American Standard.

All of the early developments in forced-air systems concerned themselves with large buildings and factories. They rarely used furnaces directly in the airstream, but instead relied on indirect heaters using steam and, in a few cases, hot water.

The use of recirculated air was not considered until after the s. The design of centrifugal blowers was continually improved in England and Europe during the late 18th and 19th centuries. These early fans were mostly operated by steam engines.

The Marquis de Chabannes advocated use of a centrifugal fan to force heated or cooled air through ducts to rooms. Walworth and Nason installed the first U. Customs House in Boston in General Montgomery Meigs planned a much larger system in for the House and Senate wings of the U. These fans as built These vanes were curved and placed on the line of a logarithmic spiral of 45 degrees.

The fans were centered in a ring of brick work The earliest fan systems were constructed completely onsite. However, it was soon evident that there was a manufacturing opportunity. Shoemaker Benjamin F. Sturtevant patented a combination fan and heat exchanger for cooling or heating purposes in He soon had established a company to manufacture and sell fans and heating systems. Other companies, such as Buffalo Forge Co.

By the s, the method of using a fan to blow air over a steam- or water-heated surface, then distributing the air to rooms in large buildings, was well established. By the turn of the century, these systems were quite sophisticated, some even featuring thermostatic and zone control. The plenum system lent itself to cooling as well with additional coils cooled in summer by refrigerated brine. These hot blast systems were also being equipped with air washers for filtering and humidifying by the s.

The popularity of hot blast systems spurred the radiator manufacturers to develop cast iron heat exchangers with an extended surface that could replace the banks of pipe that previously had been used. The most successful was the Vento sectional cast iron surface developed by John Spear in and marketed and manufactured by American Radiator Co.

The Aerofin used spirally wrapped copper sheet to produce a finned, lightweight heat exchanger. It quickly supplanted cast iron. These schemes were often complicated to adjust, if they could be adjusted at all. They were inconvenient, since one had to go to where the heating unit was located. Most heating systems simply relied upon the building engineer or homeowner to manually adjust firing rates, draft, valves, or dampers.

Modern thermostat control suddenly appeared from several inventors, all about the same time. Andrew Ure in England invented the bimetal thermostat. He received a British patent in , but his device saw little use. In the U. Professor Warren Johnson taught at a school in Wisconsin, where the only means of room temperature control was to tell the janitor to go to the basement and adjust steam valves. Johnson developed an electric annunciator system in that was used to signal the janitor when heat needed adjusting.

He continued experimenting and in , patented a thermostat that relied on compressed air to operate steam valves. He then established the Johnson Electric Service Co. Johnson went on to invent the humidostat for control of the humidity in buildings in The Butz Thermoelectric Regulator Company of Minne-apolis, MN, began manufacturing and selling the invention; however, the product did not sell well to homeowners. The company went through several name changes, ultimately ending up as the Minneapolis Heat Regulator Co.

About , William Powers was daydreaming during a dull Sunday sermon when the idea occurred to him that vapor pressure could be used to manipulate a draft damper in a furnace. He formed the Powers Regulator Co. Ironically, the first installation was in a church, where a thermostat was used to control mixing dampers in a plenum heating system. The first Powers thermostats were about in. Powers concentrated his efforts on large heating systems, and his system was used in many notable buildings, including the Chrysler and Empire State buildings.

Although thermostat-controlled draft regulators had been available for several decades, they were little used in homes. Automatic firing of heating equipment was hampered by lack of widespread availability of electric power and reliable electric motors.

Once the motors were available, inventors had to figure out how to apply them to the firing of heating systems. They also had to develop controls that would permit thermostats to directly control the equipment.

These efforts began after , accelerating through the next two decades. During WW I, a coal shortage and a government initiative to conserve energy gave a push to automatic system development. Homeowners were used to banking coal fires at night, waking up early to stoke the fire with fresh coal, then waiting for bulky heating systems to respond.

Guesswork and experience dictated how much coal to use, but this was obviously wasteful. The first electric coal stoker that could be controlled by thermostat was placed on the market in , and by the s, automatic coal systems were available from many manufacturers.