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how do you wire a L8148aJ to a millivolt gas valve??

thanks, Tim!


  • Bryan_25
    Bryan_25 Member Posts: 1

    I have an older hydro-therm boiler.That had electro-zone valves.I removed them installed two new honeywell zone valves and a honeywell L8148J aquastat realy.
    The boiler has a millivolt gas valve.
    I wired the zone valves .
    The way I have it is the red wire from the two zone valves are together and then I ran a wire to the t on the control.the other red from the two zone valves are together and I ran it to the tv on the control.
    I have the b1 going to the th and I have the b2 going to the th I dont have a th1 or th2 they both say th.
    one yellow wire from the two zonevalves are tied together and go to a transformer.the other yellow wires go to the t-stat.the other to legs of the t-stat go to the transformer.When I turn on the power the zone valves open when I put on the t-stat.
    the problem I have is the burner dosent come on.
    I do have the power run to the control L1and L2.
    and I have the circulator hoked up.
    Please help..
  • Jim Pompetti
    Jim Pompetti Member Posts: 552
    Can you

    Give us a drawing
  • carol_3
    carol_3 Member Posts: 397

    I'm on the run because I'm in route from New Zealand to Antarctica, so I'll let one of the other guys help you with the details you offered. But this may help. One of the L8148s--and I think it's the J--has special instructions in the small print for using it with millivoltage. If you don't have the instructions sheet, go online to http://customer.honeywell.com. When you get there, scroll down to the bottom right corner and enter L8148 in the little white box and click on the arrow beside it. All the literature about that control will come up. then click on the verious pdf symbols along the left side to look at all the instruction sheets. The thing about millivoltage will be in a footnote with one of the drawings. Sorry I can't be more specific. and I hope this helps.
  • Carol I am going

    to e-mail him a diagram for his system. Have fun in the land down below.
  • Bryan

    e-mailed a diagram hope it helps.
This discussion has been closed.