If we elect to replace an air conditioning condenser or heat pump unit, and it becomes necessary to make a mechanical modification to the evaporator coil to provide operational compatibility, we agree to pay the covered costs for one (1) of the following (determination is at our sole discretion) only: expansion metering device, or coil, or air handler. This Agreement does not cover any costs associated with modifications or upgrades required to match efficiency value, rating, or ratio.