Water filter for tankless water heater

[Alan Kish]

I am buying a new tankless water heater for the first time. I have extremely hard water and I have a water softener. Will the softener help or hurt the tankless unit? and should I run an additional inline water filter before the tank as an extra precaution? If so any recommendations on which one. Many thanks.

 

[Fitter30]

If you have hard water a softener would be beneficial to cut down on annual maintenance. Filter if theres problem with contaminants. Every device added has a pressure drop associated with it filter 5-10 lbs, softener 15lb and the heater.