Q: How to remove the front main evaporator in Chevrolet Astro?
A: To remove the front main evaporator in vehicles from 1985 to 2001, start by discharging the system and disconnecting the battery. Drain the coolant and remove the windshield washer and coolant overflow reservoirs. Disconnect the electrical connectors from the HVAC unit and the hoses from the heater core. If the hoses are stuck, cut them with a utility knife. Remove the accumulator and the tube connecting the evaporator to the condenser. Take out the blower motor relay bracket and the fasteners securing the HVAC unit to the firewall. Finally, remove the HVAC unit and separate the cases to withdraw the evaporator. For 2002 and later models, follow a similar process but also remove the coolant bypass valve bracket. To install the evaporator, reverse the removal steps and refill the cooling system for earlier models. If a new evaporator was installed, add 1 ounce of refrigerant oil and have the system evacuated, recharged, and leak tested. For the rear evaporator, disconnect the refrigerant lines under the vehicle and remove the left rear body side panel inside the vehicle. Disconnect the electrical connections and remove the bolts connecting the auxiliary A/C unit. Separate the cases and withdraw the evaporator. Installation is the reverse of removal, and if a new evaporator was installed, add 1 ounce of refrigerant oil and have the system evacuated, recharged, and leak tested.