If you have a tankless water heater that you are not planning to use for some time and the forecast shows an incoming cold weather and freezing temperatures, it is very important to protect the unit and plumbing system.
So, in order to avoid the unit failure, use this step-by-step guide and learn how to winterize a tankless water heater properly.
Most of the new tankless water heaters, coming from the manufacturers like Rheem, AO Smith, Rinnai, Noritz, Takagi, Bosch, Paloma and other, utilize the advanced technology and features for the freeze protection - protecting the system from freezing, down to -30 F, even lower.
But, you as the owner of the new tankless water heater, should not rely on such features.
Because all the units are using an electric power, even the protection system (which is usually a heating element or sensor), so if there is a power outage, guess what... your tankless unit will fail. And this is what many people experienced at the end of 2017, during the “arctic” winter.
This is why you should properly winterize a tankless water heater and be ready for the cold days.
Note: Almost every manufacturer of tankless heaters specifies that the heater must not be installed in the area where the temperature can reach 36 F or lower. If the precautions are not taken, like correct draining, the damage to the tankless unit and its components will not be covered under the warranty. Adding the anti-freeze solution is also not recommended as it can cause the damage to the heater's components.
This is especially important if the tankless water heater is installed in places like cabins, garages, and if you are absent for a long time.
One of the main steps when winterizing an unattended tankless heater is to drain and unplug the unit. If there is no water in the heater's pipes, especially in the heat exchanger, the unit will not be damaged due to the freezing conditions.
So, how to prepare the heater for winter?
Some manufacturers recommend using the air compressor, blow short bursts of air through the inlet connection to make sure there is no water left inside the heater.
Now the tankless water heater doesn't contain any water and it is fully winterized.