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.

Outdoor reset not working properly

CDeZutti
CDeZutti Member Posts: 6
in Radiant Heating
I Recently installed a radiant floor zone in an addition on a Weil McLain Ultra 105. Added a Taco 503 relay. The main house is on zone 1, radiant floor is on zone 2, not using priority zone 3. When zone 2 is on by itself the boiler temp spikes to 180. Not sure why the outdoor reset doesn’t seem to work with zone 2. Any suggestions? Maybe wiring issues?

Comments

  • Zman
    Zman Member Posts: 7,611
    You are going to need to provide a bit more info.
    How are the zones wired to the boiler? If they are each wired independently to the boiler to demand 1 and demand 2, you may need to either set an outdoor curve for both demand 1 and 2 or just wire them both to demand 1.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • BillyO
    BillyO Member Posts: 277
    can you post pics of piping? how are you stepping temp down for radiant?
  • CDeZutti
    CDeZutti Member Posts: 6
    Both thermostats and circulators are wired to the switching relay with a single wire from the relay to the tstat terminals on the boiler
  • Zman
    Zman Member Posts: 7,611
    Can you make a quick sketch of you wiring and post it?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • CDeZutti
    CDeZutti Member Posts: 6

  • CDeZutti
    CDeZutti Member Posts: 6

    Mixing valve to regulate radiant zone
  • BillyO
    BillyO Member Posts: 277
    does screen on front of ultra show sensor connected?
  • HVACNUT
    HVACNUT Member Posts: 6,332
    The boiler gets the same signal whether zone 1 or zone 2 is calling. 
    Where are the XX wires from the zone panel going? If XX is wired to P11, terminals 4 and 5, (heat demand 1) that is default for DHW and will override ODR. XX should be wired to P15, terminals 1 and 2 (heat demand 2). 
    Depending on how the Ultra was originally programmed, you might need to change some settings. 
  • CDeZutti
    CDeZutti Member Posts: 6
    I have a series 2 boiler, dhw is terminal 3,4 which I’m not using. They are empty
  • HVACNUT
    HVACNUT Member Posts: 6,332
    edited January 2021
    Oof, Series 2. Sorry I should've asked.  
    How was the main zone wired before you moved it to the SR503? 
    What type of emitters for the main zone and what is the supply water temp when that zone alone is running? Is it modulating from the ODR? Supply and return temp sensors are attached and working? Series 2 sensors have a habit of drying out and cracking. 
    Is there an indirect?
    Its going to be wiring, settings, or a sensor.

    You're not getting 180° at the mix right? You're talking supply temp at the boiler. 


  • CDeZutti
    CDeZutti Member Posts: 6
    I had a 1 zone taco relay before, just moved everything over to zone 1 on the 503 and added the radiant to zone 2. The mixing valve is working properly so only getting 140 to the floors. I can turn my target temp down but either way zone 1 always hits the target even on warm days when the ots should lower the target temp
  • HVACNUT
    HVACNUT Member Posts: 6,332
    Check the ODR sensor.

Categories