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Flow Sensor

Mike Tierney
Mike Tierney Member Posts: 5
This flow sensor, which is used on a closed loop glycol solar thermal system is reading incorrectly. I believe it is approximately 10 years old. I am looking to replace it and have had no luck in searching for a new one. Does anyone recognize this and is there a source for replacement? I will be draining the large system and will be able to see if just a good cleaning is all that is needed. Thank you for your time.


  • 109A_5
    109A_5 Member Posts: 1,388
    Are you sure the wires are not chafed or otherwise compromised at that mangled termination?
    To me it looks like a Dwyer Series PFT Paddlewheel Flow Sensor

    PFT-IAN-B111-S Standard brass 1-1/2 ̋ NPTM analog output

    PFT-IDN-B111-S Standard brass 1-1/2 ̋ NPTM pulse output


    Page 279

    You would have to figure out which it is analog or pulse. The type of input module at the PLC unit may be a clue. There may be a tag if the sensor is elevated on the all-thread.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
    Mike Tierney
    EBEBRATT-Ed Member Posts: 15,764
    Is it a flow switch? like with a paddle and a set of NO or NC contacts or is it a resistor that you can Ohm out. Does not look familiar to me
    Mike Tierney