If your goal is to decrease energy use and lower your utility bills, opting for a tankless water heater is a great decision. After all, water heating accounts for about 18 percent of your energy use, the second highest contributor to your utility bill after space heating and cooling.
With a tankless water heater selected, choosing the right venting option is vital for your safety and proper equipment operation. Unlike storage water heaters, your venting options are far more flexible with a tankless unit.
In fact, combined with ease of installation, smaller square footage required and a more attractive appearance, the advances in tankless design are making it more appealing to a growing number of environmentally conscious homeowners.
When it comes time to have your tankless water heater installed, the technician will inspect your home to determine the best venting option possible. Become familiar with the following seven considerations so you have an idea where the best place is to mount your water heater and configure the venting.
Indoor tankless water heaters need access to outdoor air.
Not only do the water heaters vent to the outside, but they also draw in outdoor air for combustion purposes. You have two options: direct vent and power vent.
Direct-vent units have one intake vent and one exhaust vent. This option takes up very little space. Power-vent units use an exhaust fan to actively draw exhaust fumes to the outside. This option needs a larger area to ensure enough airflow for proper combustion.
Outdoor tankless water heaters free up indoor space.
Thanks to self-warming components, tankless units can withstand sub-freezing temperatures. This means they can be installed outside, freeing up valuable indoor space in smaller homes and condos. When installed outdoors, the water heater requires no additional venting.
Multiple venting options are available.
While the most obvious place to vent a tankless water heater is through the roof, it’s not your only option. You can also vent through an exterior side wall, opening up more possible installation locations. Unlike traditional tank water heaters, which must be vented through the roof, tankless units blow exhaust out horizontally so vents can terminate through a wall instead.
Condensing tankless water heaters cost less to install.
Condensing technology is found in tankless water heaters and furnaces. It involves using two heat exchangers to extract as much heat as possible from the fuel source. The result is a unit that performs far more efficiently and expels a much cooler exhaust gas. This means the exhaust vent can be made of less expensive polypropylene or PVC, effectively lowering the cost of installation. Of course, operational costs are lower when you choose a more efficient unit as well, resulting in double payback of your investment.
A concentric vent design increases safety.
With this type of design, a 5-inch concentric vent contains both intake and outtake pipes. That way, the concentric vent itself remains cool to the touch since the hot outgoing exhaust vent is insulated inside. Also, if the exhaust pipe develops a leak, the carbon monoxide-laden air remains in the concentric vent and does not leak into the air you breathe.
Recess boxes keep the tankless unit hidden from sight.
If you want an exterior installation, keep in mind that certain newer homes are often built with recess boxes for non-condensing tankless water heaters. The box allows the unit to fit within the home’s framing instead of hanging off the side of an exterior wall. Look into whether your home has this feature so you can take advantage of it if you want.
Aesthetically pleasing venting options are available.
Look into pipe covers and creative termination points to obscure the vents and enjoy a more aesthetically pleasing finished product.
With these considerations in mind, be sure to work closely with a tankless water heater dealer to plan your purchase and installation.