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Honeywell L7224/L7248 Aquastat troubleshooting

JayMiner Member Posts: 3
I have a Buderus boiler with a Honeywell L7224/L7248 electronic aquastat. Taco control board, circulators and thermostats are working okay, but boiler is cold - won't start. No A/C power at burner. A/C power present at Aquastat L1, but nothing else is powered. Aquastat--LED display is out. I jumpered L1 to B1 and the boiler started. Fuse is okay. Is it safe to assume the Aquastat electronics are bad?


  • icesailor
    icesailor Member Posts: 7,265
    The only thing between you and death, is that grey box. With a whole series of safety switches that when the Moon is in the seventh house, and the stars are all aligned, it will gladly start and let you live. If it isn't working, and you have to get inside and play with jumpers, it isn't happy.


    Do NOT PO the happy God's. Angry God's can hurt you. You know enough to be a danger to yourself and others.

    Like people like me. who had customers who swear they haven't put any drain cleaner in a sink of standing water that hasn't drained in 6 days. And after being specifically asked if they have done so, just before the plumber sticks his arm in the sink, the answer is still "No". But the plumber immediately knows that they are lying because as he immediately pulls his arm out, he is getting second and third degree burns on his arms from the chemicals.

    Leave it to a Pro if you don't know.
  • JayMiner
    JayMiner Member Posts: 3
    My "Pro" isn't answering his phone, and my house needs hot water, so I'm replacing the aquastat in the morning. The gods shouldn't hurt me if I shut off the power first.
  • icesailor
    icesailor Member Posts: 7,265
    Changing the control is a far wiser idea than tempting the electron Gods.