Checking the Float

The float is made of polypropylene foam. It is unlikely that the float would fail unless it sticks inside the tank so it cannot move.

1. Verify the coolant level is above the float.

2. Slowly drain coolant from the expansion tank and watch the float. The float should drop with the coolant level.

3. If the float did not drop with the coolant level, remove the expansion tank from the unit.

4. Flip the expansion tank upside down and right side up to see if the float moves inside the expansion tank. Replace the expansion tank with a new one if the float is stuck or does not move with the coolant level.