First off, that’s what government incentives are for. Exactly the sort of program that OP is pointing towards.

Second, this stuff breaks eventually. That’s part of home ownership. I realize this isn’t a perfect solution, but you really do need to plan for this sort of thing. In the case of my wife and I, we were easily able to cover it with a home equity loan (along with solar panels and a new rood and a few other things). We could only do that because we’ve been in the same house for over a decade, live in an area with rising house prices, and have good credit. These things will easily pay for themselves in the long run, so the home equity loan makes good sense.

But I’m fully aware not everyone can do that. This is a place where government needs to step in to do it faster.