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.

Too many cycles?

bmac.to Member Posts: 2
We recently replaced an 80 year old gravity boiler with a brand new Viessmann Vitola with outdoor reset, etc. after much advice from this forum. Living with the old boiler, we got used to wide temperature swings and very few on/off cycles during the day. With the new system, we had 62 cycles during the last 24 hours (an avg outside temp of 2 degrees C) which seems like a lot.

Is this normal? When it gets colder, does the number of cycles go up? If its not normal, what could be wrong?



  • Weezbo
    Weezbo Member Posts: 6,232
    when the temp gets colder...

    the boiler should roll like a top....and keep on rolling.
  • Eric Tardif
    Eric Tardif Member Posts: 38
    Check thermostat

    Is the thermostat old? Replace it with a energy star thermostat. It fixed my cycling.
  • bmac.to
    bmac.to Member Posts: 2

    There really is no thermostat - the control on the boiler has an outdoor reset and it adjusts the water temperature based on that. The thermostat upstairs is only connected to the pump but I have the thermostat turned up so the pump is always on (which is an approach I have seen recommended on this forum).
  • Glenn Sossin_2
    Glenn Sossin_2 Member Posts: 592
    Teknet 4

    Look at your boiler system controls. If you use tN4, you can directly control the number of cycles.
    I attached a page from the data sheet on thermostats.
This discussion has been closed.