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Aquastat L7248C 1048 problems

pnichols
pnichols Member Posts: 1

I replaced my Aquastat L7248C 1048 sensor and the boiler started and ran for about 20 seconds then wont allow unit to restart. Error 3 for a minute or two then goes to Err 4. are there settings i need to change or is it possible i wired it incorrectly?

with it running initially i'm assuming wiring was not an issue.

Comments

  • LRCCBJ
    LRCCBJ Member Posts: 349

    You probably wired it incorrectly. Check the B1 terminal………..typically a spade connector. The error shows a poor connection at B1.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,309
    edited October 18

    You should not be able to, but what is the chance that the Sensor (3 wires) was plugged in backwards because the stop that prevents you from reversing it was compromised?

    Why did it need a sensor replacement?

    Perhaps the control is bad and the sensor was just fine.

    Since you have an OEM model of that control you may not find it avaiulable anymore. The L7224U is the universal replacement for that control

    https://www.supplyhouse.com/Resideo-L7224U1002-120-Vac-Oil-Electronic-Aquastat?_br_psugg_q=l7224u1002

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?