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 boilers without outdoor reset

Parachute
Parachute Member Posts: 25
Are there any modulating boilers without outdoor reset or where outdoor reset can be disabled? I want a boiler to respond only to the water temps in the buffer tank and calls from thermostats.

Comments

  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    I can think of several where ODR can be turned off. Triangle Tube and Navien come to mind.
    Zman
  • NY_Rob
    NY_Rob Member Posts: 1,370
    The HTP UFT series includes a outdoor sensor package from the factory... but in the installer menu you can choose not to use it.
    Bob Bona_4
  • Ironman
    Ironman Member Posts: 7,547
    edited April 2017
    Leave the OD sensor off any American made mod/con and it will fire to the high limit setting. Some will give you an error code.

    Worst case scenario: attach a resistor to the OD sensor terminals that has the same resistance that the OD sensor would have at 10*.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Bob Bona_4
  • Parachute
    Parachute Member Posts: 25
    @Ironman. Thanks. That's a good suggestion.
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    I am not a heating contractor, but I have a Weil-McLain Ultra 3 mod-con that comes with outdoor reset. If I did not want outdoor reset, it suffices to leave the outdoor sensor disconnected, and the boiler will run at maximum temperature.

    I cannot imagine why you would want to do this. It seems to me I save more fuel due to the outdoor reset than I do from the condensing.
  • rbeck
    rbeck Member Posts: 56
    edited April 2017
    Most mod-con boilers will allow you to do this. The US Boiler Alpine will allow this but we also do not suggest this as it will affect the efficiency and operation of the boiler. We can change the differential above and below separately to assist in what you are doing and use the PID adjustment for changing the fan ramping speed to extend boiler run time.
  • Parachute
    Parachute Member Posts: 25
    Ok I'm not opposed to ODR. I guess the other way to attack this issue would be to disable the internal setpoint in my Triangle Tube boiler. I want the boiler to switch only on the buffer tank calling for heat not the boiler internal setpoint because that thing starts falling as soon as the igniter shuts off. The buffer tank has a much more gradual temperature drop.