The answer to 'sump pump frozen' is that a frozen sump pump is a common issue during cold winter months. The sump pump, which is responsible for removing excess water from the basement, can freeze up due to extremely low temperatures, preventing it from functioning properly.
Some common causes of a frozen sump pump include a lack of insulation around the pump, a power outage that causes the pump to stop working, and water that has accumulated in the sump pit and then frozen. Symptoms of a frozen sump pump include the pump not turning on, the pump running but not removing water, or the sound of the pump straining to operate.