Blog Post

10 Common Causes Of Furnace Odors

  • By Admin
  • 17 Nov, 2017

When you switch on your furnace, you expect a gust of heated air to immediately begin regulating your home's indoor temperature. What you may not be expecting is the range of strange smells that waft in as your furnace runs.


Heating systems can give off strange and strong smells. Some of these odors will resolve on their own and shouldn't cause you any worry, while others can signify a potentially dangerous issue with the furnace unit. Identifying the likely cause of the scent can help you take the right steps to freshen your air.


In this blog, we list 10 common causes of abnormal furnace odors.


1. Cracked Components

Your furnace as a unit may last for significantly longer than some of its individual components. For example, many furnaces suffer cracked heat exchangers. When a heat exchanger becomes damaged, the gap releases a chemical smell that can resemble formaldehyde. Have the heat exchanger replaced right away since this issue can lead to furnace inefficiency, fires and carbon monoxide problems.


2. Damp

If your furnace sits in a damp part of your house, this moisture may settle on the unit. When the furnace turns on and gets hot, this dampness begins to burn off which can create a smell of dampness throughout your home. Luckily, this odor should resolve itself as the furnace continues to run.


3. Excess Dust

During the off-season, dust may gather in and on your furnace. As you begin to heat your home for the first time during the year, the furnace will likely burn this dust. If your heated air smells dusty for a short period of time, the odor should dissipate quickly. You can prevent this smell by dusting off the furnace before switching it on.


4. Gas Leaks

Natural gas used for heating is treated with sulphur to give it its distinct rotten egg smell. This odor is intended to alert homeowners to potential gas leaks as soon as possible. If you smell sulphur, leave the area and call an HVAC technician as well as your gas company.


5. Intake Contamination

Many furnace units intake air from outside the home. Anything that is within proximity to this intake system could potentially alter the characteristics of your heated air. For example, if your furnace smells like sewage, the odor likely comes from a sewer system opening that is near your intake system.


6. Mold

In some cases, dampness can lead to mold. Moldy furnaces are more common in areas with high humidity and in homes where the furnace stays cool and damp. Mold may smell similar to the moisture discussed in section two, but the smell generally won't go away as easily. Mold may also smell extremely musty or earthy.


7. Obstructions

If your furnace becomes obstructed in any way, one of the first signs that you're likely to notice is a change in air smell. The type of obstruction determines the resulting odor. For example, a blocked chimney may make your furnace smell like it's smoking, while a pest struck in the system would smell like decay. Generally, you'll need to turn off the system and have it inspected to resolve these issues without the risk of improper furnace venting.


8. Old Filters

Furnaces are fitted with internal filters that help regulate the air quality in your home. Over time, the filter can become clogged with dirt and debris. Not only can a blocked air filter affect the efficiency of your furnace, but you may also smell the obstruction as well.

An old furnace filter may smell somewhat like motor oil. However, you should be aware that if changing the filter does not get rid of the smell, the unit could have a serious oil leak, which requires professional attention.


9. Overheating

In addition to the gas leak-related odors discussed in section four, you should also never ignore electrical, hot metal or sparking odors. These smells typically indicate an issue with overheating and may point to a faulty auto-shutoff.


10. Vent Contamination

Like the area around your outdoor intake system, what's near your indoor vent registers can affect your furnace smells. One of the most common vent contamination issues is the smell of pet hair or urine. Check each vent register for a pet mess that needs cleaning. Taking care of the mess should resolve the smell as well.

In addition to the information provided, you should consult an HVAC expert if you have any concerns about the odor coming from your furnace. For example, if the smell appears suddenly, is particularly pervasive or persists for a long period of time, you may need a professional opinion to determine the true underlying cause.

Use this guide and the experience of your trusted HVAC technician to help you decide on the right course of action when your furnace starts to smell strange.

For reliable heating services, including routine and emergency furnace repairs, trust Hartman Heating, Air, and Fireplaces.

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Fireplace safety is crucial if you want to enjoy the warmth and charm your gas or wood fireplace provides. One way to keep your fireplace safe throughout the winter is by monitoring creosote buildup. An excessive buildup of creosote can prove dangerous for a variety of reasons, plus it can impact your fireplace's longevity.

Read on to learn more about creosote, how it affects your fireplace, and the steps you can take to keep your fireplace in good condition.


What Is Creosote?

Creosote is a combination of tars and various other chemicals produced as a byproduct of burning wood or fossil fuels. Small amounts of creosote mingle with the smoke that rises to the top of the flue. Along the way, the creosote combines with moisture and adheres to the flue liner or open brickwork of the chimney, creating a thin layer of tar that solidifies as it cools.

Creosote has had plenty of interesting uses throughout history, including as the active component of various medicines. These days, creosote is used in commercial applications to treat and preserve wood for increased longevity and durability. Creosote is responsible for giving smoked meats their distinctively smoky flavor, plus it's also the special ingredient behind artificial liquid smoke flavoring.


Why Is It Dangerous?

Creosote buildup never goes away on its own. Once a layer of creosote forms, it's there for good until it's physically removed. Without proper cleaning, multiple layers of creosote will steadily build up every time you use your fireplace. This buildup causes the flue to narrow, reducing the amount of ventilation available to your fireplace.

The resulting lack of fresh air prevents your fireplace from burning its fuel efficiently, resulting in a smaller, dirtier flame that causes even more creosote buildup. The cycle continues until your flue becomes completely blocked with creosote, rendering your flue liner unusable.

Creosote is also highly flammable, especially when it accumulates in large amounts. Excess amounts of creosote can ignite when exposed to enough heat from your fireplace. Creosote-fueled fires can spread quickly and with little to no warning, making these fires incredibly dangerous. Failure to clean excess creosote buildup is a common factor behind most home heating fires, according to research from the National Fire Protection Agency.


How Does It Form?

There are several stages to creosote buildup. Each successive stage can prove more difficult to deal with than the last, which highlights the importance of tackling creosote buildup at its earliest stages. How soon creosote buildup occurs usually depends on several factors, including the efficiency and overall condition of your fireplace. If you're using a wood fireplace, the quality of the wood being used as fuel can also affect creosote buildup.


First Stage

Creosote buildup starts out as a light coating on the flue. Depending on how efficiently your fireplace burns its fuel, the creosote buildup will mostly consist of soot with small amounts of tar mixed together. As a result, the initial stage of creosote buildup appears thin and flaky.

The first stage of creosote buildup is always the easiest to deal with. Fireplace technicians can remove creosote buildup using special-purpose brushes, preventing additional, harder-to-remove layers from forming.


Second Stage

As the creosote buildup continues, the soot is replaced with more tar, giving the creosote a thicker, harder, and sometimes shinier appearance. The overall texture of the buildup remains dry and crumbly, however.

Brushing alone won't remove second-stage creosote buildup. Rotary loops and chemical solvents are the usual go-to tools for fireplace technicians when battling creosote buildup at this stage.



Third Stage

Left to its own devices, the creosote buildup eventually turns into a highly concentrated mass that appears oily and feels sticky when fresh. Repeated exposure to heat usually gives this mass a hardened, shiny appearance. At this stage, a simple cleaning may be extraordinarily difficult, if not impossible. Some technicians even encourage a complete replacement of the flue liner as a more cost-effective alternative to cleaning.



How Can It Be Prevented?

Since it's a naturally occurring byproduct of the combustion process, there isn't much you can do to completely stop creosote buildup in its tracks. However, taking a proactive stance on fireplace maintenance will help prevent excessive creosote buildup.

Fireplace technicians can spot and take preventive action against the beginnings of excessive creosote buildup during regularly scheduled fireplace checkups. These checkups also ensure that the flue's inner mechanisms are working properly, significantly reducing the rate of creosote buildup.

Most experts recommend having your fireplace inspected on an annual basis. Flue cleanings should be done when there's a 1/8-inch deposit of creosote in the flue.

Prevention is always the key when it comes to creosote buildup. The sooner you can tackle the buildup, the easier it'll be to deal with. To learn more about the effects of creosote buildup or to schedule a professional inspection, contact us at Hartman Heating , Air and Fireplaces today.
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From supplementing your HVAC system in the winter to adding an appealing focal point in any room, you have several reasons to install gas or wood fireplace in your home. Have you decided that a fireplace is a great investment but are not sure if a gas or wood model is the best option for your home, family, and budget?

Do not agonize over this decision. Instead, here are a few tips and factors to help you determine if you should choose a gas fireplace or a wood fireplace for your home.


Cost of Installation

The cost to install either a gas or wood fireplace is dependent upon several factors. You have two common types of gas fireplaces in homes: gas inserts and built-in models. You install a gas insert inside an existing firebox, while you install a built-in in the wall. With the built-in fireplace, you do not need to have a firebox already in your home.

A freestanding wood stove typically costs less to install a traditional built-in wood fireplace. This is because if you opt for a built-in wood fireplace, you pay for the cost of labor and components, including the masonry.

You have other factors that impact the cost of installing either a gas or wood fireplace. If you lean toward gas, you will need to install a new propane or natural gas line if one does not already exist. Additionally, you will need to decide if you want to install a ventilation system.

For wood fireplaces, you will need to factor in the cost of replacing an existing fireplace, including the surround and firebox, and the price of installing a new chimney or repairing the existing chimney.


Cost of Fuel

The typical fuel source for a gas fireplace is either natural gas or propane. The price of either will vary throughout the year depending upon several factors, including supply, the time of year, petroleum prices, and state of the economy.

Because prices and availability fluctuate, contacting a professional to help you determine which option is best for you is a great way to ensure you choose the right product.

The costs to install either a built-in or gas insert model are about the same.

The cost of fuel for a wood fireplace is typically much less, especially if you have a readily available supply of trees on your property. The cost of wood is far less than natural gas or propane, but this can be more time-consuming to gather, cut, stack, and store the wood. Keep this in mind, especially if you do not have a place to store wood on your property.


Cost of Maintenance

The cost to maintain a wood fireplace is typically higher. If you choose a wood-burning stove, you will need to clean it periodically and schedule an appointment to have a professional inspect the unit at least two to three times per year. If the wood stove does not properly combust the fuel, the stove will not run efficiently. Maintaining a built-in wood fireplace will also cost more on average.

In addition to inspecting and cleaning the firebox, you will also need to have a professional inspect the chimney at least once a year . Luckily, you have professionals who can handle these jobs and will ensure that your built-in wood fireplace is also in amazing shape.

A gas fireplace is typically very easy to maintain and care for. If the fireplace has vents, hiring a professional to inspect and clean it at least once a year will prevent clogs.


The Look of Gas or Wood

The aesthetic appeal and the homeowner's taste is a huge factor when considering whether to pick gas or wood. If you have a more modern home, a sleek glass fireplace is a great option. You have several varieties of built-in and insert fireplaces, including models that feature glass logs, stones, or coal. You can even purchase a gas fireplace with a remote control.

If you have a more traditional home or simply prefer the classic elegance of a brick or stone facade and mantel, consider a wood fireplace. Many homeowners also prefer the smell and feel of a traditional built-in wood fireplace as well.


Resale Value

A recent survey of homeowners found that as many as 40 percent  would pay more for a home that features a fireplace. Whether you choose gas or wood, installing a beautiful fireplace in your home is always a smart investment. If you want to sell your home in the future, ask a local real estate agent about which type of fireplace that homeowners in your area prefer.

From the potential resale value they add to the cost of installation and maintenance, several factors exist that you should consider when deciding to choose a gas or wood fireplace for your home. If you have any further questions, contact the professionals at Hartman Heating, Air and Fireplaces .

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