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Intellicon control sensor problem

dh1989 Member Posts: 20
I installed an Intellidyne Intellicon HW+ a few years ago to resolve short cycling of my boiler due to some small baseboard zones. It has worked well until the domestic hot water sensor failed causing the control to allow the DHW to go cold while in bypass mode sending heat to the baseboards. I found corrosion on the circuit board of the sensor and went to find a replacement but it appears Intellidyne is out of business. I ordered a 4002C sensor from Supplyhouse (the only place that had it in stock) and was sent a different looking sensor. The original used 4 conductors and the new one only has 2. I'm not sure if they sent the wrong part or if this is supposed to be a replacement. I connected it and the Intellicon control doesn't read the new sensor.

If anyone is familiar with this control and could offer advice let me know. I will contact Supplyhouse on Monday to return the sensor if it is indeed the wrong one. Thanks.

Pictures of old (left) vs new part (right):


  • pell
    pell Member Posts: 17
    Have you had any luck finding a sensor? Over the years I have installed many of these controls and now like yours the sensors are failing. I would like to purchase some if any one knows where to buy them.
  • ratio
    ratio Member Posts: 3,380
    Can you take a good close up pic of the front & back of the board inside the sensor? There's at least a passing chance that's it's just a standard thermistor, if so a replacement would be simple.
  • dh1989
    dh1989 Member Posts: 20
    The Beckett heat manager sensor (Beckett part# 7518) is a direct replacement for the Intellicon sensor. The newer model Intellicon branded sensor (on the right in my photos) will not work with the older HW+ unit.

    Beckett nor Intellicon will be able to confirm that this sensor will work on the Intellicon, but I learned by trial and error ordering different parts.