How Does A Pellet Stove Work?

A lot of homeowners are probably thinking about installing pellet stoves in order to stay warm this winter, and for a very good reason, they burn cleanly, they produce lots of heat and they require little maintenance. People who own pellet stoves absolutely love them. Pellet stove is a heating appliance that is similar to a wood stove but instead of burning firewood, it burns compressed hardwood pellets that are about ¼ inch in diameter and ¾ inch long. The pellets for a compact pellet stove are commonly available in 40-pound bags. They are made from compressed sawdust and waste wood that would otherwise be dumped into landfills or left to rot in the forest. Pellets are considered carbon-neutral because of the carbon monoxide level exhausted by the stoves, they are similar to the carbon released when wood decomposes naturally on the forest floor. To ensure the stove burns hot and clean, it is important to purchase high quality hardwood pellets from a manufacturer that is a member of the Pellet Fuels Institute. Pellets are typically bought by the ton, and the average household goes through between 2 and 3 tons of pellets per heating season. A ton of pellets, or 50 of those 40-pound bags, costs between 200 to 300 dollars.

How Does A Pellet Stove Work?

Here is how a pellet stove works, you pour pellets into the storage hopper that is located at the top of the pellet stove. An electric auger delivers the pellets from the hopper to the burn chamber. Sensors within the stove monitor the fuel supply and tell the auger when to drop a new pellet. It will put in just enough pellets to keep the fire burning small but extremely hot.

There are never more than a small handful of pellets in the burn chamber at any one time. A pellet stove has a combustion blower that pulls outside air into the stove through a fresh air vent and then blow out smoke and fumes through a stainless-steel exhaust vent. There is also a convection blower that draws room air into the stove and it blows heated air into the room through a series of heat-exchange tubes.

The stove will automatically deliver heat, based on the thermostat setting. All you need is to keep the hopper filled with pellets. As with wood-burning stoves, there are two basic types of pellet stoves, freestanding models and inserts that fit into existing fireplaces. And while pellet stoves are typically installed as a supplement to the home’s primary heating system, that does not mean that they cannot pump out the Btus. Medium-sized pellet stoves can produce between 40,000 and 50,000 Btus per hour, enough output to heat more than 2000 square feet of living space. If you have a smaller room to heat, do not worry. Pellet stoves come in a wide variety of size and range in price from about $1000 to $5000. Pellet stoves burn so hot and clean that there is a very little ash left behind, especially compared with woodstoves.

You have to empty the pellet stove’s ash pan just once a week, even if the stove is used every day. And pellets produce virtually no creosote, which is a major cause of chimney fires. Most pellet stoves have an auger that delivers pellets from the hopper to the combustion chamber. The auger’s movement is operated by a solid-state control that is set manually or, with some stoves, by an optional wall-mounted thermostat. A fire’s size depends on the rate of feed. Pellets delivered at 1 pound per hour will produce a very gentle, glowing fire that will last a long time. At 5 pounds per hour, a pellet fire will be ablaze.

Combustion Chambers

The pellets are placed in a fire pot or burner ring in the combustion chamber. Combustion air is blown into the chamber to encourage a super-heated flame. You must light some pellet stoves, others are self-lighting. If they are turned off, or if the power fails, they stop burning.

Pellet Stove Heat Exchangers

The air in a room is drawn in by a fan and blown across the heat exchanger, which is heated to about 250 degrees F. and the warmed air is returned to the room. Unlike wood stoves, pellet stoves rely on convective, not radiant, heat. Most pellet stoves do not get too hot to touch as a result, an important consideration for families with small children. This also means a stove may be placed closer to combustibles such as walls. They do need to stand over a minimum of 3/8 inch thick non-combustible floor such a tile.

Pellet Stove Venting

Residual combustion gases are vented outside, and they are normally through a 3-inch flue that exists out the unit’s back or top. Some have an interchangeable top or rear vent. Pellet stove venting kits can be purchased online or from pellet stove dealers. Though most of the pellet stoves do not require a conventional chimney, saving you from considerable expense and design inflexibility, most types draw better if the flue goes out through the wall and turns upward. For safety control, it is wise to extend the vertical section past the eaves.

Start up and shut down

Pellet stove manufacturers configure their pellets toves differently for start up, some use them as an automatic ignition system, a gel or other approved materials for start up. Failing to follow the manufactuer’s start up procedures can cause problems with the stove’s operation. Do not unplug the pellet stove to shut it down. Instead, use the automatic control to set the shut off for the unit, as the pellet stove needs to cool down completely beofre shutting itself off.

Maintenance

Your pellet stove requires routine maintenance to keep it at peak operating condition. Exmaine the burn pot every day, clean it according to the manufacturer’s instructions. Open the ash drawer weekly and empty the ash pot as much as it is needed. Follow the instructions in the manual for cleaning the heat exchanger. Some pellet stoves require professionals to clean the heat exchanger.

How much does it cost to run a pellet stove?

The idea of a very efficient wood pellet stove often appeals to homeowners who are tired of paying high home-heating cost during long, cold winters. However, the initial cost of the stove is steep and fuel costs are relatively high, making a pellet stove one of the more expensive heating options that you can choose.

The initial cost

Although the initial cost of a wood pellet stove is not technicially part of the stove’s operating cost, it is important to consider the up-front cost since it will cust into any savings from the operation of the pellet stove. Pellet stoves are not cheap, a typical unit will cost you around $1,700 and $3,000 and the installation cost will increase the overall price to somewhere between $3,500 and $4,000. A conventinal wood-burning stove costs around $3,000 and $4,200 installed and a natural gas furnace costs around $3,000 to $5,550, just to compare.

The fuel cost

The overall cost of wood pellet fuel is given in dollars per ton, the average price of the fuel is around $250 per ton. The cost of a cord of wood, the fuel burned by a conventional wood stove, is around $200. The average home uses about 7.3 tons of pellet fuel or 6.5 cords of wood per season. A ton of pellet fuel produces about 75% of the energy produced by a cord of wood, but pellet stoves are more efficient than wood stoves, which then narrows the fuel-cost gap between the two types of stove. You should also note that most pellet stove have fans, controls and fuel-feeder systems that run on electricity, the monthly electric bill for a typical stove is about $9

Cost per BTU

The best way to compare the cost of pellet stove heat with the cost of the other types of heating systems is to compare the cost relative to energy output. At a fuel cost of at least $250 per ton and an efficiency rating of 85%, a pellet stove heat costs around $18 per million BTU. At a 75% efficiency rating, the cost increases to more than $20 per million BTU.

Comparison to other fuels

On a cost per BTU basis, pellet stoves are significantly more epensive than wood stoves, which will cost you around $13 per million BTU. Natural gas furnaces are almost as cheap as wood stoves, at $13.52 per million BTU, and coal-fired systems are much less expensive, at $10.89 per million BTU. Among commonly used heating fuels, only fuel oil, propane and electricity are more expensive than wood pellet fuel.

Combustion Chambers

Turning on a manual start stove

Read the instructions that come with the stove, before you ignite your manual start pellet stove, it is important that you read the instruction manual. It will have important details and warnings that you need to know before you start using the stove. Fill the stove’s hopper with pellets, the hopper is the mechanism on the back of the stove that feeds pellets into the burn pot. Open the lid on the hopper and pour pellets into it until it is 3/4th’s filled. Close the lid once you are done. Remove the ash from the burn pot, open the front door of your pellet stove. The burn pot is the tray in the bottom of the stove, where the pellets burn.

Scrape out the ash with a metal object like a gardening shovel or fire iron. Fill the burn pot with pellets, scoop a couple of handfuls of pellets into the burn pot until it is full. These pellets will ignite the stove’s fire. Pour ignition gel on top of the pellets and stir them, you can buy ignition gel online or at hardware or department stores. Thoroughly saturate the top of the pellets with the gel and mix the burn pot with your fire iron or small shovel. Lighter fluid can drip through the burn pot and to the bottom of you stove. Avoid using it. Light the pellets with a lighter or a match, ignite a lighter or a match and carefully put the flame on the ignition gel. A small fire should start to catch on top of the pellets.

Wait for the fire to strengthen, then close the door, wait for 1 to 3 minutes. The fire should gradually get stronger, if you close the door too quickly, the fire won’t get enough oxygen and it will go out. Turn on the stove’s fan, the fan button can be found on the side or the front of your stove. The fan will recycle the air in the stove and it can prevent it from making your house filled with smoke. The fire should sustain as long as it is filled with pellets. Once the fire gets going, you can also adjust the temperature higher or lower.

Pellet stove maintenance

Pellet stoves are very efficient heaters, but they require more maintenance than the typical furnaces and wood stoves. Avoid performance and saftey issues with your pellet stoves by following these steps.

1. Use high quality pellets

When you use the best pellets, your heating costs may increase slightly compared to using lower grade fuel. However, avoiding the soot buildup and other issues with low grade pellets make the extra expense worth it. You must remember that pellets should have a low moisture content no higher than 10%. If your pellet stove also burns nut shells, corn kernels and wood shavings, buy the best quality fuel of these types that is available. Use fuel without multiple fillers and glues to avoid excess smoke and ash in your pellet stove. Look for pellets that are PFI certified for your intended use.

2. Check the ash and the dust content

Some pellet stoves can handle pellet fuel with a low or high ash content, other pellet stoves may gum up or fail to burn them properly if they are fed with pellets of the wrong type. Check to make sure that your pellets are the right ash type for your stove. Top-fed pellet stoves are often designed to work best with low ash pellets. Continuous feed hoppers and chutes on heaters are susceptible to sawdust accumulation in the same way that fans and chimneys collect ash and soot. Check your pellet supplies to ensure the integrity of the pellets is good. Avoid pellet bags with an abundance of sawdust and loose fuel at the bottom.

3. Have your pellet stove serviced and checked each autumn

Schedule an inspection by your local fireplace and stove-repair service before the cold weather starts each fall. The pros know how to check for broken, dirty and missing components on your pellet stove. Some of the areas that they check include the hopper, the augur, the pressure switches, the electrical wiring and switches, the igniter, the electrical, vacuum and pressure sensors and the combustion or the convection motor. The technician will also check your pellet stove’s firewalls, burn pot, and chambers for proper operation. If needed, you are advised to hire a professional cleaner for your type of exhaust system. Another thing that the professional will do is to lubricate and replace parts that are needed to be lubriacted and replaced. They will switch out a bent or corroded fan for a fresh replacement. This preseason check ensures that problems are spotted and they are fixed before temperatures drop so you and your household can have a comfortable winter.

4. Raise efficiency with a soot sweep

Pellet stoves require at least a weekly tidy to brush away collected sawdust, ash and soot. Cleaning up the hopper and feed areas is not difficult, but buy a cleaning set with an efficient, ergonomic broom, whisk, and dust pan to make your job easier. Allow the stove to cool periodically so you can remove excess soot on a regular basis. Use fire resistant tools for this job, and always dispose of ash properly to avoid fire. Pellet stoves are extremely safe when you follow the simple cleaning regimen weekly.

5. Clean your stove’s window periodically

Experts recommend that you clean your pellet stove windows at least once a week to prevent the glass from completely blacking out your total view. Soot, grime, and ash build up rapidly on the glass. If you wait until the end of the season, the cleanup may take a lot longer than a routine wipe down. Check your owner’s manual for the correct window-cleaning methods for your pellet stove. Allow the glass to cool completely before you being cleaning it.

You can use newsprint or lint free cloth as a cleaning rag. Ask your fireplace and stove repair service to recommend a cleaner for your pellet stove glass if you prefer to use a commercial product. For a homemade solution, dampen the rag with vinegar. You can also use a rag dampened with water and dusted with wood ashes to wipe away the glass. Then, use water-dampened newsprint to wipe the class clear. Allow the glass to dry thoroughly, never use abrasive products or cleaners for ovens, as these products can mar the glass. You also do not want to introduce unsafe chemicals that create fumes when heated.

Conclusion

There are a few other things that you must consider when thinking about purchasing a pellet stove. For instance, they are very heavy, an average size unit measuring about 25×27 inches, and it weighs nearly 400 pounds. If you plan to install it yourself, get plenty of help. The stove must be set onto a fire resistant surface, such as tile or stone. So if the room has hardwood, carpeting, vinyl, or any other combustible flooring, the stove has to be set onto an approved hearth pad. Some stoves accept an optional pedestal, which effectively raises the stove about 7 inches to a more comfortable and attractive height. The exact type of venting required depends on the stove’s proximity to windows and doors, a vented stove that is not properly installed will allow smoke and fumes to be sucked back into the house. When looking for a pellet stove, bring photos of the room and include measurements to nearby windows and doors. An experienced dealer will design the appropriate venting system of your specific situation. Most pellet stoves come with an attached hard wired thermostat, but for added convenience, wireless remote thermostats are also available for about $150. Install a ceiling fan in the room with the pellet stove then run the fan in reverese to blow heat trapped at the ceiling down into the room.