Evolution of Furnace



Evolution of Furnace


The idea of using furnace for central heating purpose is eras old. The earliest idea of central heating home was introduced by Romans which is known as hypocaust. In their idea they use lit fire in the corner of the basement and exhaust ventilate the heat through flue in the walls to the chimneys. This heating system was only suitable for stone or brick constructed home. It’s too dangerous as it has the possibility of fire and other life threating hazards.
The general ideas of burning fuel for furnace was burned wood.  Thane in seventeen century it’s been replaced by coal and using of coal remain till early 1940s. In 1970 gas become primary fuel and here it started replacing it due to energy draw back.  Todays forced air high efficiency gas furnace are the most popular and most economical way of heating homes.
However the furnace which was using wood and coal requires continues feeding to make heat for home. Usually required fuel five to six time in a day. Require fuel is feed in the burner and waste of burnt fuel need to be removed.



High efficiency furnace Raw Material


In construction of today high efficiency furnace need the raw material which is stainless steel, brass, and aluminum. Copper and fiber glass. Heat exchanger uses a stain steel to minimize its corrosion resistance. Furnace cabinet, burner and blower is made up of aluminum and steel to maintain furnace efficiency and durability. The furnace cabinet is insulated with fiber glass to avoid heat loss.


How the furnace start working

A request for heating is executed by thermostat causing ignition of burner and move the heat in to primary heat exchanger. This heated air is transfer to secondary heat exchanger (only in 90% or up efficient rating of furnace) and heat is distributed through flue and ducts. A flue draft blower is placed in the exhaust flue to supercharge the burners and increase efficiency 
 

Furnace AFUE Ratings

Furnace models can be categories as AFUE (Annual Fuel Utilization) ratings. Which will determine the cost of energy fuel for heating with gas, oil or other fuel. That is why the furnace with higher AFUE is the most economical way to full fill home heating requirements.




Furnace Quality Control

To ensure furnace quality it undergoes some standard series of furnace quality assurance tests. That includes it complete operation. Quality check of entire machinery and other component of furnace. Verifying the heat capacity of furnace along with other durability tests.



Typical efficiency Gas Furnaces

Conventional efficiency furnace have commonly efficiency rating start from 78%. The conventional efficiency gas furnace generally use a naturally aspirating burner instead of pilot lit system.
Modern furnace have electric ignition system and consume approx. 3 to 5 present less energy than a furnace with regular pilot ignition light.


                                             

Typical-efficiencygas furnace with induced draft fan



The powered exhaust is used by typical standard efficiency furnaces, generally depend on built in induced draft fan. With greater heat exchange and zero dilution of air and greater resistance to flow while the off cycle, regular efficiency is much higher for today's standard-efficiency furnaces than for furnaces equipped with pilot lights. Energy savings are between 23 and 28 percent.


These systems will be ventilated through a chimney or out the facet wall of the house using best chrome steel. Some issues are related to the use of high-temperature plastic vent pipes with typical-efficiency furnaces. Rules could forbid the use of bound vent materials in your space. You should discuss all choices together with your native service person, approvals agency or gas utility.Installation codes could need transferal a combustion air provide to the furnace from outdoors.


Compressing type highefficiency gas furnace




The burners are like those on typical furnaces, associated draft is equipped by an elicited draft fan. However, further heat-exchange surfaces product of corrosion-resistant materials (usually stainless steel) extract heat from the combustion by-products before they're exhausted. During this compressing heat exchange section, the combustion gases are cooled to some extent at that the water vapor condenses, so emotional further heat into the house. The condensation is piped to a floor drain.
Because no chimney is required, installation prices are reduced. The flue gas temperature is low enough for the gases to be ventilated
A PVC or plastic pipe out the facet wall of the house. Depending on the design, these furnaces will dissipate to thirty 8 % less fuel than older gas furnaces equipped with pilot lights. Moreover, polluting emissions free into the surroundings also are reduced.
Some compressing furnaces or boilers disagree only therein they use a pulse combustion technology to ignite little amounts of gas at frequent intervals.
Unlike typical and standard-efficiency furnaces, whose efficiency decreases with furnace over sizing, compressing furnaces are literally slightly additional economical once they are outsized and run for shorter periods. Thus, if you're selecting a replacement compressing chamber, you'll be able to get a furnace that's slightly larger than the house heat demand while not suffering associate “efficiency penalty.”



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