GM Astro/Safari 1985-1996 Repair Guide

Evaporator Core


Two evaporator cores are used, one in the front (engine compartment) and one at the rear (overhead) door. The rear overhead air conditioning system works in conjunction with the front system.


Before removing the evaporator core, the air conditioning system must be discharged. Refer to the air conditioning Discharging procedures in General Information & Maintenance and discharge the air conditioning system. The system should be discharged by a qualified technician with proper recovery equipment. It is illegal to discharge refrigerant into the atmosphere and you may need a permit to purchase new refrigerant. If you do not possess the proper equipment, training and permits to perform refrigerant recovery, allow a repair shop to do that step for you.

Front System

See Figure 1

Click image to see an enlarged view

Fig. Fig. 1: Front evaporator case mounting

The front evaporator core is located in the engine compartment on the right side of the firewall inside the heater/evaporator/blower motor case.

  1. Disconnect the negative battery cable from the battery.
  3. Remove the radiator coolant collecting bottle and the windshield washer fluid bottle.
  5. Disconnect any necessary electrical connectors.
  7. Discharge the air conditioning system as outlined in General Information & Maintenance . Disconnect the air conditioning refrigerant lines from the evaporator.
  9. Remove the relay bracket and move it aside.
  11. Remove the evaporator/blower case nuts and the case, then separate the evaporator from the case.

To install:
  1. Install the evaporator into the case and tighten the retainers.
  3. Install the relay bracket.
  5. Connect the air conditioning refrigerant lines to the evaporator.
  7. Connect any necessary electrical connectors.