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.

Honeywell L4006a Aquastat

Jnugget Member Posts: 10
Hello all. . .just finished zoning off the house and repiping the boiler,Now I'm putting in a sr504 controller. I'm just a little confused on wiring up the aquastat. Theres bx coming off the burner goes to the aquastat then to a switch then from the switch it used to go to the old controller. . Does that get connected to the XX on the bottom left side of the controller?!? If so does it make a difference which terminal the white and black go to?? I just want to be sure so I dont fry anything. the boiler is for Heat only. the aquastat is existing on the boiler so I dont know how old it is, but it still works fine so I left it in place. Thanks again - John


  • furnacefigher15
    furnacefigher15 Member Posts: 514
    Burner circuit

    XX means it closes on call for heat (typically burner circuit)

    Sounds like old control was 120 volt

    Check the taco xx terminal rating to see if 120 volt is ok
  • billtwocase
    billtwocase Member Posts: 2,385
    edited December 2011

    You should have  an electrician do this for you. Temperature controls are also a safety control, and need to be wired and tested by someone who has the knowledge. 
This discussion has been closed.