Gas Furnace Vent Pipe – Types, Choosing The Best & Maintenance Tips

What type of vent piping is used in gas furnaces? Here are the common options.

When it comes to combustion, several by-products are released.

These consist of small particles and gases. The resulting gases include hydrocarbons, particulate matter, water vapor, carbon monoxide, and sulfur dioxide.

Others include carbon dioxide and nitrogen dioxide.

Gas Furnace Venting Options

All of these need to be let out or allowed to escape into the atmosphere. Inhaling these will be dangerous. Now, several fuels are used for combustion purposes.

We’re more interested in vent system types applicable to gas combustion in furnaces.

So, what type of vent pipes or systems are installed for such?

High-Efficiency Furnace Venting is Vital

All types of furnaces thrive on efficiency.

Here, every part of the furnace from the return register, return duct, air filter, blower, blower motor, blower chamber, flame sensor, burners, and vents, etc need to be in excellent shape.

Being in excellent shape refers to their functional capacity.

Now, all the byproducts of combustion must be properly vented. Different types of vent systems can be installed with the hope of getting expected outcomes.

One thing that’s common with all expected outcomes is efficiency.

Without further delay, let’s consider the different types of gas furnace vent pipes available.

Gas Furnace Exhaust Pipe Types

Irrespective of type, gas furnace vent pipes help achieve one objective; the removal of toxic combustion gases from a home or building.

Now, there are three main types; the natural vent, direct vent, and sidewall power vent.

What are the differences or uniqueness of each? Let’s have a look.

i. Natural Vent

Also called the type B vents, this gas furnace vent pipe design is quite common with a lot of heating appliances.

Apart from venting out combustion byproducts, this natural vent pipe draws in fresh air from the outdoors to support combustion.

You’ll find this mostly installed on newer furnaces. For a lot of people, this might be interpreted as being the most efficient and safe compared to other gas vent types.

However, this isn’t true. Natural vent systems for gas furnaces tend to have their downsides.

The downdraft mostly experienced with such systems harms safety and efficiency.

Speaking of safety, back-drafting translates to exhaust gases returning into your living room or quarters instead of moving up out of the vent pipe to be expelled.

This exposes members of your household to these toxic gases which can be fatal after inhaling sufficient amounts.

  • B-Vent Pipe Position

As mentioned earlier, the B-vent pipe is primarily designed for the expulsion of combustion gases. Now, the B-vent pipe is mostly positioned vertically and exits through the roof for easy removal of gases.

One of the benefits of B-vent pipe installation is that they aren’t difficult to fix.

ii. Direct Vent

If natural vents seem like an ineffective option, you might want to try out the direct vent pipes.

What about these vent systems? Based on design and operation, direct vent systems tend to be more efficient than natural vent systems for gas furnaces.

Its piping system includes two pipes of varying sizes both held within a single unit. One pipe (the outer) pulls in fresh air from the outside to support combustion. As expected, the other is designed for venting outgases.

Through this pipe, exhaust gases are effectively dispelled.

Direct vent systems tend to have more flexibility than natural vents because they can be installed either vertically or horizontally.

In the case of horizontal venting, these pipes won’t go through the roof but will instead go through your walls.

Due to its several benefits like less environmental pollution, ease of installation, and cleaner indoor air, installation costs tend to be higher.

When looking at efficiency and safety ratings, direct vent systems easily measure higher than natural vents.

iii. Sidewall Power Vent

The sidewall power vent includes some improvements in design. These improvements significantly impact efficiency in a good way. A vent that passes through a wall is attached to a fan.

This fan helps with pulling out exhaust from the gas furnace, thus making the venting process much more efficient than the others mentioned above.

When have barely functional or non-functional chimneys, the idea is to either have them fixed or remodeled. With a sidewall power vent, you have a much better option.

Your old chimney doesn’t have to come in the way as you can easily install the sidewall power vent to operate independently from the old chimney.

What more? You get the added advantage of efficient operation. In terms of cost, sidewall power vent systems offer a cost-friendly option for venting your gas furnace.

Apart from the high efficiency which is quite obvious due to the inclusion of a fan, this system is also safe for use.

What Gas Furnace Vent will be Best for me?

This decision is entirely up to you.

We’ve discussed the workings of each with the benefits offered. We recommend you ask your chimney technician for a recommendation on what to go for.

What are the Signs of Problem with a Venting System?

Gas furnace vent pipes or systems aren’t foolproof.

In other words, these could develop faults that may not be noticeable. Faults could include back-drafting issues among others. You might begin to experience certain health conditions due to exposure to exhaust gases.

When this goes on for too long without finding out the root cause, fatalities may result. This is something you want to avoid at all costs.

Examples of symptoms you may notice as a result of exposure to exhaust gases include dizziness, chronic bronchitis, and nausea.

Other symptoms include excessive yawning, heart palpitations, fatigue, and headaches. At this point, you’re expected to take two actions; contacting a healthcare professional and calling chimney professionals.

Chimney professionals can diagnose and identify the problem. Appropriate treatment measures are carried to resolve the problem.

  • Preventive Maintenance

One of the ways to ensure your gas furnace doesn’t develop faults is by calling for yearly inspection and maintenance. It doesn’t matter what type of gas vent you have.

They’re kept functional while faults or potential issues are identified early on and treated.

The types of gas furnace vent pipes serve several purposes. However, in terms of efficiency and safety, these do not rate the same.

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