3/8" Heatshrink tubing, suitable for use as a thermal well for both the Ranco ETC and Johnson A419 temperature probes for temperatures under 100°F. (Tubing is priced per foot.)
Neither the Ranco ETC nor Johnson A419 probes are recommended for direct submersion in any liquid. The manufacturer recommends use of a thermal or bulb well. The copper well (WEL11A-601R) offered by the manufacturer is not suitable in all applications, especially aquariums where it may be harmful to fish, corals and other sea life. Thus a tight fitting plastic tube is recommended for aquarium use (some hobbyist will simply coat the probe in silicone instead).
3/8" eat shrink tubing is ideal for use as a thermal well because it is easier to fit the probe into, provides a very tight fit (when shrunk), and has a thinner wall than 1/4" ID vinyl tubing that may be used instead.
Installation: To install, simply insert the probe leaving 1/2" of tubing past the end of the probe and shrink the tubing using a heat gun. Then heat the end of the tube with the heat gun until it's hot and soft (but not so hot that it burns). Then pinch the end with a pair of needle nose pliers (without teeth) and hold for about 15 seconds while it cools. The excess amount past the seal can be trimmed off. It's best to practice with a small piece of tubing first.
Ordering: The tubing is priced per foot. You should allow for enough tubing so that the entire length that you are submersing under water is enclosed in the tubing. For example: If you are placing the sensor at the bottom of an 18" tank, you will need 2' of tubing.
Free Installation with controller or sensor order: If you are ordering a Ranco or Johnson controller or replacement sensor at the same time as the tubing, we would be happy to install it on the sensor for free. Please just make a note in the comments section of your order. Also, if you are ordering more than one and need different lengths of tubing on each, please specify how much is to be installed on each controller. Note: a maximum of 6 foot can be installed per sensor.