Tankless water heaters provide a supply of hot water as and when required. Rather than storing hot water, it is heated only when it is needed so saving on fuel.
To get the best out of a tankless direct vent water heater, an installer will first inspect a house to determine the best place to fit it. There are several key considerations to bear in mind when choosing where to install a tankless water heater.
There are two types of venting mechanism in tankless water heaters: direct vent and power vent. Direct vent units draw air in from outside and have two vents, one to take air in and one that acts as the exhaust.
Power vent only needs an exhaust vent but they must be placed in a larger room, such as a basement, where there will be enough airflow for combustion.
If a tankless water heater cannot draw in sufficient air it will not be able to burn hot enough to provide efficient heating.
Some models of tankless water heaters can be installed outside. This frees up indoor space, so it is a great idea in smaller homes where space is already limited.
Heaters need to be able to withstand freezing temperatures to work efficiently outside, but most tankless heaters include automatic, self-warming components that allow them to keep functioning even in the coldest temperatures.
More flexible placement
Although we have said that these units should ideally be placed on an outside wall, the venting systems are flexible and can be vented through a roof as well as a wall. Traditional gas tank water heaters can only be vented through the roof and take up much more space in the home.
Vented hot water heaters can be safely vented through the wall of a home because they have a fan to blow the exhaust gases out horizontally.
Condensing tankless heaters are 95% more efficient
A condensing tankless water heater can reduce the cost of installation and the cost of the heating. Some people experience savings of up to 95% compared to non-condensing units; they also have a relatively cooler exhaust that can be made from cheaper PVC or polypropylene rather than metal.
The centric vent design that is common in many models of tankless water heater provides safety benefits over more traditional vents. For example, because a five-inch concentric vent has cold air surrounding the hot exhaust, the exterior of the venting is kept cool and is safe to touch.
Also, if the exhaust develops a leak the gases cannot enter the home because they will be contained within the air inlet piping.
Because tankless heaters are so compact, they can be installed in a recess box within a wall, rather than installed within the home or against the exterior. Many new homes are now built with recess boxes already in place and this allows a unit to fit inside the home’s framing rather than to hang off the side, making for a much more attractive finish.
Sealing the vents
When having a direct vent water heater installed it is important that the pipe is properly sealed to avoid air from the home being drawn into the heater. A good seal also stops cold air from outside being forced into the interior. Poorly installed direct vents often suffer air leakages.
Direct vent water heaters take the air in from outside the home and then send it back outside through the same concentric pipe. The pipe is constructed with inner and outer sections. The outer section draws the air in and the inner pipe is the exhaust.
It is a good idea to place a heater on an outside wall so that it can have direct access to outside air thus minimizing the need to use lengthy pipes. A long pipe will not work as efficiently, so always consider relocating your water heater when upgrading,
Tankless hot water heaters use a unique venting system that blows the hot gaseous exhaust outside where it can safely dissipate into the air. One of the advantages of a tankless hot water system over a traditional one is that tankless systems offer more versatile venting solutions.
Modern direct vent water heaters are very compact and efficient and this has allowed manufacturers to build more attractive and easier to fit systems that can also save money. Also, installing on an outside wall is still possible in crowded homes; gone are the days when the water heater would have to take up half a basement.