Senztek S3 Tank Sensor

Solar Hot Water Parts has a wide range of solar hot water sensors. The most common mistake that people make is to think that all sensors are the same. There are many different types of thermistors and resistors used in making solar hot water sensors. Roof sensors should only be used in the solar collector. Tank sensors cannot be used as roof sensors as they are rated to lower temperatures. Please contact us if you need help or you are unsure of what you need to purchase. Email us some photos of what you are looking for, as this will help ensure you provide the best possible information.

  • Senztek S3 Tank Sensor
    Senztek S3 Tank SensorSenztek S3 Tank Sensor

    Senztek S3 Tank Sensor 3m

    Download S3 Manual

    The Senztek S3 Tank Sensor can be used for inlet or tank sensor with any of the Senztek range.

    The S3TM system uses a carefully designed heat transferring copper foot surrounded by an insulating cover. The cover, together with attachable split rings, also acts as a low tension spring holding the sensor foot against the inner wall; self adjusting for expansion and contraction. An outer flange attaches to the cladding to secure the assembly and provide a surface for the spring to act against.

    The S3 tank sensor is easily retro fitted to any solar hot water system using the Senztek controller. It allows for a rapid, reliable and accurate sensor installation into a hot water cylinder in a straight forward manner. 

    The S3 sensor is great for fixing old solar hot water systems which used the old sensor well T.     fig1.  


    These sensor well T's with the very short sensor port are not very accurate and tend to cause more damage in the long run. Because the sensor well is so short when hot water is replaced during the day, cold water passes over the inlet sensor giving an inaccurate reading at the controller. This can easily tell the controller the tank temperature is a lot lower than it actually is, turning on the pump. On a hot day where the system has topped out this can simply be triggered by the hot water expansion valve opening because of the excess pressure from the heat; cold water passed over the cold water sensor several times a day. Each time this turns on the circulating pump; the result is excessive over use of the circulating pump as well exposing it to potential high temperatures. The S3 can be installed into the side on the tank at a higher level below the return line, this will also help eliminate thermal shock. Please read the installation manual for more information.