Question 1

Why does Hott-Wire use fiberglass insulation instead of magnesium oxide (MgO)?

jallen · Accepted Answer

Most MI cables use magnesium oxide (MgO) as the mineral insulation — but MgO is hygroscopic, meaning it absorbs moisture from the environment over time. Moisture absorption degrades the insulation and can eventually cause cable failure. Hott-Wire uses inert fiberglass insulation instead, which does not absorb moisture. This makes Hott-Wire more resistant to the humidity and freeze-thaw cycles encountered in outdoor snow melting installations, and contributes directly to its 10-year warranty longevity. This is a specific engineering improvement over standard MgO MI cable construction.

Question 2

Why does Hott-Wire use fiberglass insulation instead of magnesium oxide (MgO)?

jallen · Accepted Answer

Most MI cables use magnesium oxide (MgO) as the mineral insulation — but MgO is hygroscopic, meaning it absorbs moisture from the environment over time. Moisture absorption degrades the insulation and can eventually cause cable failure. Hott-Wire uses inert fiberglass insulation instead, which does not absorb moisture. This makes Hott-Wire more resistant to the humidity and freeze-thaw cycles encountered in outdoor snow melting installations, and contributes directly to its 10-year warranty longevity. This is a specific engineering improvement over standard MgO MI cable construction.