1.   If it is, hot water will flow into the radiator from the pipework and displace the trapped air.

2.   Bleeding releases the trapped air.

3.   After it is running you will also have to drain the radiators in the house to let trapped air bubbles escape.

4.   Carefully run a non-metallic utensil down inside of jars to remove trapped air bubbles.

5.   Carbon monoxide from automobile exhaust and other sources is polluting the trapped air.

6.   Occasionally trapped air may prevent a hot-water radiator from filling up completely, and the radiator will never get hot enough to heat the room.

7.   Remove trapped air with slender plastic spatula.

8.   Run a non-metallic utensil down inside of jars to remove trapped air bubbles.

9.   Scientists are also measuring the pressure of trapped air within ice bubbles.

10.   The air can be purged, he said, by opening the bleeder valve at the top of the radiator and allowing all trapped air to escape.