Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Condensing hot water tanks

Henry Member Posts: 996
This morning we are replacing a condensing hot water tank at a car dealer. This tank was engineer specifyed. It lasted a little over 5 years. We have been replacing a number of condensing hot water tanks that have the burner and combustion chamber on top. If they short cycle some of the condensate does not get heated in the chamber to get blown out. It rests in the bottom of the chamber and slowly rots it out. This cannot happen with a HTP that modulates and has the burner at the bottom.


  • jumper
    jumper Member Posts: 2,139
    Does energy efficiency pay after maintenance/shorter life costs?
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,644
    It goes to show that condensing without modulation doesn't work well in the real world.

    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Henry
    Henry Member Posts: 996
    We have not had to service ANY HTP condensing hot water tank. The dealer had specified HTP as a replacement. We have installed 2, 4 years ago at his other dealership.
    JUGHNE Member Posts: 10,898
    Henry, were those Phoenix HTP water heaters?
  • Henry
    Henry Member Posts: 996
    Yes we install only HTP Phoenix condensing hot water tanks unless an engineer specifies something else.