Spanish to English Tech/Engineering Engineering (general) Boilers

Hi
I would really appreciate your help.
I have a few questions as it's from a big project I just finsihed, therefore, they're coming one after the other.

Context is:
"Accesorios Calsdera:.... De seguridad, que comprenden la válvula de seguridad, sistema de alarma, sellos o compuertas para alivio de sobrepresión en el hogar y tapón fusible en aquellas calderas a que....."

Thanks a lot :)