The hot water works in a few ways:
If the water level in your toilet is already at the rim, do not try this yet. You need room for the extra water. Wait for the level to recede or manually remove some water first. can boiling water unclog a toilet
Heat a large pot of water on the stove. Stop when you see small bubbles forming at the bottom, but before it reaches a rolling boil. The hot water works in a few ways: