Plumbing in the Home/Plumbing
QUESTION: Recently everything in my house that requires a water source such as the toilet, water heater and ice maker began shaking at the same time. It happens for about 15 seconds every minute and sounds as if water is quickly flowing and stopping. This happens even when water isn't turned on at any source
ANSWER: Hi Rob,
This is typically a sign of excessive water pressure either due to a change in municipal water system or a failure of an installed pressure regulator. Excessive pressure will override the fill valve in a toilet momentarily until the pressure drops a bit from use. The maximum pressure the domestic plumbing fixtures are designed to handle his 80 pounds per square inch. Any more than that and problems occur, often like you are describing.
It could also just be a failing toilet fill valve (also called a ball cock) that has gotten weak and is no longer capable of holding the pressure. To test both of these situations, simply turn off the water at the shut off valve under the toilets and see if the noise goes away.
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QUESTION: How would the ball cock affect the fridge and water heater shaking? They shake hard enough that you can physically see them shake.
Both the refrigerator and the water heater are connected to the water system. Water is an incompressible fluid. Moving water has a lot of kinetic energy that is suddenly transferred when it stops such as when one of the valves closes quickly. A very rapid starting and stopping of water flow can create a significant vibration throughout a water system as it transfers that kinetic energy to the solid parts of the system such as the piping and any appliance connected.
Another possible place to look for the culprit is in an exterior irrigation system such as lawn sprinklers. One side of that system is always pressurized and the valve itself is a spring-loaded solenoid. High pressures and a weak spring can cause that solenoid to chatter open closed rapidly which in turn transfers a lot of energy into the piping system. I have seen excessive pressure prevent a sprinkler system from shutting off. Once it turns on under a high pressure condition, the spring is too weak to close the valve again.