Plumbing in the Home/Thumping & sputtering
QUESTION: I have a home built in 1973 with a slab foundation. I'm on city water. Lately the cold faucets in the kitchen and one bathroom have started making a throbbing/sputtering when you turn them on. It doesn't happen all the time but it's frequent. It seems to happen less when they are turned on slowly. It gradually stops doing it and the water runs okay. The bathroom faucet sometimes runs fine and then gradually slows down to nothing. I have cleaned the aerators in both faucets but they don't seem to be clogging. The bathroom has a dual faucet and the kitchen has a Moen single action faucet. The rest of the inside and outside faucets don't seem to have any problems. Any ideas what might be going on here?
ANSWER: Hi Roger,
This phenomenon can be caused by a number of different things. One of them is worn faucet stems that have now become loose. Under certain flow conditions the stems will chatter and vibrate producing the sound that you hear. The gradual slowing of the water flow is most likely happening on the hot water side and is caused by heat expansion of the actual stem that changes the effective opening of the valve and thereby able to flow less water.
Another possible problem is a failing or malfunctioning pressure regulator. These devices have Springs and diaphragms inside that can wear and can be also caused a malfunction due to build up of debris. They can usually be rebuilt using a repair kit with new Springs and diaphragms. If is available, replacement would be needed.
Since this problem is intermittent and a Moen cartridge type faucet is not usually subject to the stem chatter problem, I would be looking at a faulty regulator myself.
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QUESTION: Thanks, Dana.
Where would the pressure regulator be located? And....is it something I could change or would I need a plumber?
The pressure regulator is usually on the main incoming water service so it serves the whole house. DIY is totally up to you and your skills. It's not like changing a light bulb.
Water piping systems can consist of several types of materials, galvanized steel, copper and various types of plastic. Each requires a different technique and tools to work with.
Given that this is your whole house's water supply, a mistake can be a problem.
Might be a good idea to get a plumber in there. And DON'T just tell them you want the regulator changed. Replacing a regulator can cost several hundred dollars and if that actually wasn't the problem, you have wasted your money. A good plumber will attempt to diagnose the problem and not accept your inexperienced diagnoses straight away. A sketchy plumber will just do what you ask and charge you for it and then throw up his hands if it doesn't fix the problem because you told them you wanted the regulator changed. It could be something entirely different. My diagnosis is based on your description and years of experience and is at best, an educated guess. LOL
Depending on its age, there may not be a repair kit available. Not all systems have a regulator. It is usually only installed if the city water pressure exceeds 80 psi.