Tenant keeps breaking things

[Ananth ArianaHegde]

I have a tenant that seems to have a knack for breaking things. Ever-since he moved, he has been calling me every month sometimes multiple times to complain on broken things. I recently had to replace the HVAC system coasting me 10K, today he send me an email claiming that the other system is also non-functional and that he tried to get it fixed himself but to no avail. When I handed him over the property, the house was working in great condition. Given the temperatures are peaking to 100+ here in Dallas region, I am not sure what my options are? I am financially very stressed right now and don't necessarily have the cash to spend money on another unit. But I don't know what the legal implications are if I don't fix it right away. I don't have any home warranty ( biggest mistake of my life) and need some advice on how long can I wait and what options  to I have to get this right and give him a message that he cannot be doing this over and over again.