This is the upper glass, not the glass around the heater. This glass is user replaceable, and available for TM! and TM2 (they are different).
Apparently the glass surrounding the heater is not offered as a spare part, and replacing the glass is a major diassembly/ reassembly project that likely voids the warranty.
It shouldn’t be to difficult to replace.
Here’s the TM2 method:
- remove the long middle screw that holds the unit together. You can find it on the units bottom plate.
- taking the top plate off the unit and unscrewing the grounding wire connection.
- Go back to the bottom of the unit and remove the bottom plate.
- unscrew the heater’s post from the circuit board and then slowly removing the heat post from the unit.
- taking out the broken glass, replace and repeat the w I’ve steps in reverse order.