The answer to 'pressure regulator frozen' is that a frozen pressure regulator is a common issue that can occur during cold weather. This happens when water inside the regulator freezes, preventing it from functioning properly and regulating the water pressure in your home.
Some common causes of a frozen pressure regulator include extremely cold temperatures, a malfunctioning or improperly installed regulator, or a lack of insulation around the regulator. Symptoms may include low water pressure, water not flowing, or the regulator itself feeling frozen or stuck.
In many cases, a frozen pressure regulator can be thawed and repaired by a homeowner. This may involve wrapping the regulator in a heating pad or towel, or using a hair dryer to gradually melt the ice. However, if the regulator is severely damaged or the issue persists, it's best to call a professional plumber to inspect and replace the regulator as needed.