Heater works intermittently on Chevy Astro?

In this case first try this ........
Try tapping on the outside of the blower motor and see if it starts to work.
If yes then its issue with the blower motor.


The blower motor comes out from under the hood, below is the procedure.

BLOWER MOTOR
Removal & Installation
Disconnect negative battery cable. Unplug blower connector. Remove coolant recovery tank.
Remove bolts from windshield washer reservoir, and secure reservoir aside. Remove blower motor
cover. Cut insulation cover between 5 clips. Retain insulation cover for installation. Remove cooling
tube from blower motor. Remove blower motor from case. To install, reverse removal procedure.

This will help.
Thanks.

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