My parents upgraded their heating system 6 years ago to a dual energy system (oil/Electric-heat pump). They are looking to get a new service contract from where they purchase heating oil from. They've always had an annual service contract that covered cleaning and maintenance of the oil burners on the furnace and the water heater, but they've never had the heat pump checked. This is their first heat pump so my dad is not sure what type of service these units require or how often they need to be looked at. It is the primary heat source during the winter months, and the A/C part is barely used during the summer. It was turned on maybe less than 10 times between May and September. For people who have a heat pump how often to you get them serviced?