2. Look at the outdoor unit. A heat pump will have two coils, while a strip unit will only have one.
3. Feel the air coming from the unit. A heat pump will produce warm air when it is in heating mode and cool air when it is in cooling mode. A strip unit will only produce warm air.
4. Turn the thermostat off. If the unit continues to run, then it is a heat pump. If the unit turns off, then it is a strip unit.