Do indoor tankless water heater prone to freeze?

[Dappropsllc]

For indoor tankless waler heater, does it need insulation?

 

[Breplum]

Insulation is only a slight buffer in borderline freezing conditions.
In space that gets below freezing, heat tape might be recommended.

 

[Sponsor]

 

[John Gayewski]

If this "indoor" condition is subject to freezing then the heater needs drained. As would any piping. The heater is just a pipe wrapped (and/or through) around a firebox.

I would say they are more prone to freezing damage than a tank heater. But that is highly conditional.