Pellet stove

Background and history

Scrap wood and ship-lap burners of barrel stoves, braziers, and oil drum fires in depression Hooverville historical media. Professionally built wood-fired ovens with sawdust hoppers were used in the early part of the 20th century. All of these units used scrap wood or sawdust. In 1930, the Presto-Log was invented from the potlatch pine mill in Lewiston, Idaho for domestic heat. From this came the miniaturized pellet stove, which emerged from Washington State in the 1980s.

The pellet stove changed in appearance over the years from a simple, boxy workhorse design, to a modern heating appliance. Pellet stoves can be used in the chimney. Most pellet stoves are constructed using large, heat conductive, steel or cast-iron pieces, with stainless steel to encase circuitry and exhaust areas.

Pellet furnaces and pellet boilers are also available in addition to the decorative stove. These units can be retrofitted into existing home heating systems with only minor changes to existing ductwork and or plumbing.

The heating industry has substantially shifted to biomass stoves and heating devices based on efficient fuel and renewable resources. ^{[ citation needed ]} This was a trend that began with the 1973 oil crisis causing the first pellet stoves. Even so, pellet stoves have become viable, economical, and popular option for home heating systems only in the last ten years. ^{[ citation needed ]}Between 1998 and 2010, 824,410 pellet stoves and fireplace inserts were made in the US. ^[1]

While some stoves are listed , such as wheat, corn, sunflower seeds, and cherry pits, many pellet stoves and pellet mixers.

Method

The pellet fuel is delivered from the storage facility or the day tank (single stoves) into the combustion chamber. With the heat generated, circuit is heated in the pellet boiler. In central heating systems the hot water then runs through the heating circuit. The heat distribution is the same as other central heating systems. Unlike oil or gas heating, the inclusion of a hot water tank is recommended. ^{[ quote needed ]}

Benefits

Most pellet stoves are self igniting and cycle themselves on thermostatic control. Stoves with automatic ignition can be equipped with remote controls. Recent innovations include integrated microcontroller monitoring of various safety conditions and can run diagnostic tests if an imminent problem arises.

A properly cleaned and maintained pellet stove should not create creosote , the sticky, flammable substance that causes chimney fires . Pellets burn very cleanly and create a layer of fine fly ash as a byproduct of combustion. The grade of fuel oil affects the performance and ash output. Premium grade pellets produce less than one percent ash content, while standard or low grade pellets produce up to six percent ash. ^[2] Pellet stove users should be aware of the extra maintenance required for a lower grade pellet, and that inconsistent wood quality can cause serious effects to the electronic machinery over a short period of time.

A pellet stove is normally associated with pelletized wood. However, many pellet stoves will also burn such grains, corn, seeds, or woodchips . In some pellet stoves, these fuels can be mixed with wood pellets. Pelletized trash is also a fuel for pellet stoves.

Unlike wood stoves qui operate exclusively on a principle of chimneydraft, a pellet stove must use specially sealed exhaust pipe to prevent exhaust gases escaping into the living room due to the air pressure produced by a burning blower. Pellet stoves require certified double walled venting, usually with a stainless steel interior and galvanized exterior. Because pellet stoves have a forced exhaust system, they have the advantage of a vertical rise to the wind, although a 3-to-5-foot (0.91 to 1.52 m) vertical run to induce some draft is recommended to prevent leakage the case of a power outage. Like a modern gas appliance, pellet stoves can be ventured horizontally through an outside wall, making it an excellent choice for structures without an existing chimney. If an existing chimney is available, manufacturers urge a proper sized stainless steel liner the length of the chimney for proper drafting. Modern building techniques have created tightly sealed homes, forcing many pellet stoves to reduce the risk of failure.

Pellet stoves are approved for use in mobile homes, while standard wood burning stoves are not. ^{[ quote needed ]}

In many states ^[ where? ] pellet fuel is exempt from sales tax. ^[3]

Tax credit

Until January 1, 2012, in most states in the US, a 75% efficient pellet stove was eligible for a tax credit of 30% of the cost of the appliance as part of the 25C provision , plus labor. ^[4] [5]

Principles of operation

A pellet stove normally consists of these components, whether basic or complex:

• A hopper
• An auger system
• Two blower fans: combustion and convection
• A firebox: burn pot and ash collection system, sometimes lined with ceramic fiber panels
• Various safety features (vacuum switch, heat sensors)
• A controller

To properly function, a pellet stove uses electricity and can be connected to a standard electrical outlet. A pellet stove, such as an automatic coal stove, is a fuel heater fuel that is fed evenly from a refillable hopper into the burn pot (a perforated cast iron or steel basin), through a motorized system. The most commonly used distributor is an auger system that consists of a spiral length of metal encased in a tube. This mechanism is one of the most important examples of pellet fuel burners.

Fan systems are necessary for clean, economical performance. The flame produced is concentrated in the small area of ​​the burn pot as a combustion blower introduces air into the bottom of the burn pot, while also forcing exhaust gases into the chimney. While some pellet stoves will be hot to the touch (especially on the viewing window), most manufacturers utilize a series of cast-iron or steel heat exchangers that run along the back and top areas of the visible firebox. With a convection blower, room air is circulated through the heat exchangers and directed into the living space. This method allows for a much higher efficiency than the radiant heat of a hand-fed wood stove, and will be in most cases to the top, sides, and back of the stove to be at most warm to the touch. Along with convection air, an exhaust fan forces air from the firebox through special winding made for pellet fuel. This cycle of circulation is an integral part of the combustion system, and it will quickly be overheated the firebox. The possible problems associated with overheating are electrical component failure and flames traveling into the auger tube causing a fire hopper. As safeguards, all pellet stoves are equipped with heat sensors, and sometimes vacuum sensors, enabling the controller to shut down if unsafe condition is detected. For daily maintenance, an ash vacuum is recommended. These are similar to shop vacs, but are designed for the removal of ash materials. These vacuums are available with a pellet stove kit which allows the cleaning of the interior areas of the stove.

Pellet stoves can be manually or automatically ignite. The igniter piece resembles a car’s electric cigarette lighter heating coil. Most models have automatic ignition and can be equipped with thermostats or remote controls.

Corn stove

A corn stove is designed for a whole kernel shelled corn kernelburning and is similar to a pellet stove. The chief difference between a stove and a stove is the addition of metal stirring rod within the burnpot or an active ash removal system. These vary in design slightly, but usually consist of a long metal stalk with smaller rods and a perpendicular angle, in order to burn the pot as it spins. An active ash removal system consists of augers at the bottom of the burn pot that evacuate the ash and clinkers. During a normal burn cycle, the sugar content in corn (and other similar bio-fuels) will cause the ashes to stick together, forming a hard mass. The metal stirring rod breaks these masses, causing a much more consistent burn. While there is a need to create multiple fuels with minimal adjustments,

See also

• Pellet Mill
• European Biomass Association
• Heat Exchanger s
• Biofuel s

References