What signifies that a water pipe may be frozen?

A pipe that is frozen typically does not allow water to flow, which would result in no water coming from the tap. This is a clear indication that ice has blocked the pipe, preventing the liquid from passing through. In locations with freezing temperatures, water can freeze inside the pipes, often at points where there is inadequate insulation or where the pipe is exposed to cold air.

The absence of water when the tap is turned on is the most direct and reliable sign of freezing. If a homeowner experiences this, they may need to take measures to thaw the pipe safely or seek professional assistance to prevent further issues like pipe bursting.

Other conditions mentioned may either indicate different plumbing issues or would not necessarily point to freezing. For example, clear water running from the tap suggests that the pipe is functioning normally. Unusually warm water might be a sign of improper water heating, while a rattling noise could indicate loose pipes, water hammer, or air in the system rather than freezing. Thus, the confirmation of frozen pipes lies primarily in the lack of water flow from the tap.