The best way to answer this question is to refer to your user manual and check the manufacturer recommendation. Generally, it is recommended to schedule preventive maintenance for your air conditioner at least once a year before the cooling season. This will ensure that your unit is running efficiently and can help prevent costly repairs in the future. Refer to the user manual of your air conditioner for the manufacturer recommendation. Our team at House Depot Home Services will provide you with a more accurate estimate of the installation time after evaluating your specific needs during a consultation. Furthermore, heat pumps are a greener way of heating and cooling your home because they aren’t burning fuel to generate heat. You can also benefit from federal rebates when purchasing and installing a heat pump system. They are generally safer to operate because they don’t burn fuel and produce fire, smoke and toxic gasses.