Total pack failure

[Brianoz]

Hi,

I'm studying some jet aircraft systems and learning about pressurisation. However, I don't think I've got a total understanding of what happens with a total pack failure (not a rapid depressurisation-door failure etc). My questions are:

I understand cabin pressure will rise, but why can't the outflow valves seal the cabin completely to simply maintain the cabin pressure? Also, will cabin temperature rise or fall?

Thanks