This is a question that homeowners often ask HVAC technicians, and it makes sense that they would. There are many home repairs you can manage on your own with the right tools and a bit of know-how. Why wouldn’t this also apply to a home heater?
But a heating system isn’t the same as reattaching kitchen cabinet doors! Modern heating systems are complex, and because of the amount of power they require to run—often burning natural gas to generate heat—trying to repair them without professional training and equipment is risky.
So the simple answer is, No, there aren’t any heating repairs you can do yourself.