This is just SO wrong!

[glatt]

What does your lease say? Does it say anything about him making repairs?

Colorado may have screwed up laws that allow a landlord to rent a place that isn't fit for habitation, but if he signed a contract saying that he will make repairs, then he has to make those repairs. Contracts are generally binding that way.

Outside of the lease, your only legal right in Colorado may be to move out, but you can still do other things.

He wants to make money by renting the place out. If you move out, he will need to fix the furnace to attract a new renter. So he's going to fix the furnace anyway. You just have to convince him to do it now, rather than after you move out. Explain this to him. Tell him that you are looking for a new place since he won't fix the furnace. It's a pain for him to have to find a new tenant, and it will probably take him at least a few weeks, which means he won't be receiving any rent during that time. I assume you have been a good tenant, who pays rent on time. He isn't going to want to lose you, since good tenants are actually hard to find.

You can also do as others have suggested by putting outside pressure on him. The media and government may take an interest in this. The Colorado Bar Association would be interested in the lawyer wife who is attempting to do some shady stuff. But to go after her, you'll need documents with her name on them. She's probably not dumb enough to put her name on anything.

I'd start by calling the landlord and telling him that the portable radiators aren't cutting it, and that you expect him to fix the furnace, and if he doesn't you'll be moving out.