Any luxury service (consensus determines what a luxury is in this case, not the individual) that is personalized, intimate, and requires spending a lot of time with you would carry the expectation that you tip. HVAC is seen as a necessity in the US, the same with cars, and the same with medical care. Tipping wouldn't be expected in those instances.
The only situation where there is an unwritten expectation for a tip is at a sit-down restaurant with waitstaff and for food/grocery delivery. These are luxuries 99% of the time.
In all other cases that I know of, they will ask you outright if you want to tip. For example, when I get a haircut or a massage, they ask me explicitly if I want to tip, and, because it was a personalized, intimate, luxury service, I oblige. For simple walk-up services like coffee or take out, I wouldn't tip.
The only other times I tip are for exceptional service (e.g. in a fastfood drive through) or if it's a local business that I'm fond of.
The only situation where there is an unwritten expectation for a tip is at a sit-down restaurant with waitstaff and for food/grocery delivery. These are luxuries 99% of the time.
In all other cases that I know of, they will ask you outright if you want to tip. For example, when I get a haircut or a massage, they ask me explicitly if I want to tip, and, because it was a personalized, intimate, luxury service, I oblige. For simple walk-up services like coffee or take out, I wouldn't tip.
The only other times I tip are for exceptional service (e.g. in a fastfood drive through) or if it's a local business that I'm fond of.