All homeowners should have homeowners insurance and all renters should have renters insurance. Insurance is what you need to protect your home and assets against damage, loss, or possible theft. We aren't an insurance company. A very few people try and file claims with us from leaky roofs, to clogged drains, to under sized electrical systems in old homes that the circuit breakers pop off - pretty much anything that breaks in the home they state that we were there at some point so we must be responsible for the item failing.
Mechanical items tend to break randomly and can break at any time. I'm a Reliability Engineer by trade so I know this having worked 26 years in that business.
Also, there isn't anything the teams do differently than you or I to turn water on and off, flip light switches on and off, plug vacuums in the electrical socket, etc., so its not like the workers would or could do something that would make it become damaged beyond what is normal usage.
Usually when something breaks, it is either flawed or old and it finally failed and maybe it wasn't even working before the team tried it.
We are a very honest company so if the team did something to damage something beyond trying to use it just as any normal person would - we would happily credit you. It has to be beyond "normal reasonable use" as all things fail over time and there is normal wear and tear and we can't be responsible to not apply normal wear and tear no more than any other physical being.
Our teams report all accidents immediately as we have never made a team pay for anything damaged.