Workplace.
So it’s on them to fix it.
But since they “fixed” the hit water, I’m not sure I want them to try and fix the heat.
The system is antiquated and supremely inefficient. Your best action might be to make a suggestion that they replace it with an air-to-air heat pump system.
They might get tax credits for it, and it would pay for itself in reduced electricity bills.
You could perhaps even find a contractor willing to give a good price in hopes of getting further upgrades with them elsewhere.