This varies by rebate program, however the most common products covered are high-efficiency forced-air furnaces, hot water heaters and tankless water heaters, boilers, smart thermostats, and somewhat less commonly central air conditioner replacements, ductless mini-split heat pumps, and HRVs/ERVs.Note that the rebates often also cover various other home energy efficiency upgrades like insulation, windows, etc however this particular rebate guide focuses on HVAC-related rebates.Sometimes a portion of the required energy audit is also covered.