Split the account by what heats the building, not by repair versus install
A boiler search, a furnace search and a ductless search come from different buildings with different tickets and different crews, so they should not be competing for the same money.
Most accounts we look at arrive with one repair campaign, one installation campaign and a geographic target of the city plus twenty five miles. The heating budget then flows to whichever ad gets clicked most, which is rarely the work you most want.
A better shape: separate campaigns for hydronic and steam, forced air heating, cooling and ductless retrofits, and light commercial. Each gets its own budget, its own landing page and its own negative list. You can then starve one and feed another in a week without touching the rest.
The reason is dispatch, not tidiness. If one technician does your steam work, you cannot buy steam calls at the same rate you buy filter changes. Budget has to reflect who is actually on the truck tomorrow.
Light commercial belongs on its own. Rooftop units, a courtyard building boiler, restaurant makeup air. Different search terms, a longer sales cycle and a buyer who wants an invoice and a certificate of insurance before anything else.