Heating Element Sealing

There are two levels of needed restoration of the heating element terminals on an espresso machine.....terminals which have missing or degraded sealant (often referred to as "that red stuff" but it is actually called  Glyptal....sometimes a simple shellac was used which is brown in color).    The first level is indicated by crumbling  of the sealant around the electrical terminal of the element and often the ceramic insulating beads are missing.

If the element terminals were to happen to get wet then we would have the second, and more severe situation....a heating element shorted at the terminal end due to water entering through the degraded sealant and shorting electrical terminal to the base.    This situation is a bit more complicated repair but first, lets just seal up this non shorted but in need or restoration heating element.

First, shake or stir the glyptal and apply with a toothpick, making sure the entire area surrounding the terminal is covered.   The glyptal will flow into all of the voids.

The glyptal will dry to touch in about an hour and fully cure in 24 hours.    When it is dry and cured, apply the insulating teflon collars by finding the slit on the side with fingernail or tool, opening the collar at the slit, and placing over the bare terminal between the spade shoe and the glyptal.

When finished your heating element will be sealed and fully insulated....nicely restored!

If your element is shorted, a bit more repair is involved.  

To diagnose this type of short caused by faulty end sealing on the terminals check it with a multitester as follows.
  • Set the tester on ohms and check reading from element terminal to terminal...it should be a steady reading of x ohms, but steady with little change
  • Place one lead of the tester on the terminal and one on the base....if you get ANY ohm reading this is shorted....particularly diagnostic if the ohm reading wanders all over the meter and does not stabilize.   This is due to the presence of water in the material at the element ends
Heating Element Short Repair:
  1. First, you must dry out the terminal ends to remove the water.    Generally placing the element in an oven at high heat for 3 to 4 hours will dry it out.  You can also use a propane torch directly to the terminal ends but the oven method is likely the safest overall.
  2. After baking the element, pick out the crumbly dark bits in the end of the element with a needle probe until you see nothing but nice solid (usually ceramic) material inside the tube at the element end.   This area can be as much as 1 cm deep.
  3. Test  the element as before....terminal to terminal and then terminal to base plate.    If you still have a short then reheat and repick, then retest.
  4. When there is no more ohm reading from terminal to base you have cured the  short.
  5. Take a small amount of the epoxy putty and knead until blended (you will have approximately 8 minutes until the the cure begins!)
  6. Using a pick or thick needle type probe, pack the epoxy into the end of the heating element around the central wire.  This will stabilize the terminal end so it will not touch the side and recreate an even worse short.
  7. Once the epoxy has cured (15 minutes or so) proceed with the sealing procedure as outlined above.

We have cured many elements using this technique.    This malady is most common on Olympia and La Pavoni machines which have the element directly attached to the base.    It is a lesser issue on machines which use jam nuts to secure the element to the base, but any time you have a machine that throws the ground fault breaker or the main panel breaker, or sparks when you plug it in, or shocks you, suspect this type of heating element short and proceed with a certain satisfaction that it CAN be fixed.    There's no guarantee with this, but it's good to try before you replace the element - DO YOUR Diagnostics first - bake it, pick it, clean it and keep testing!