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 Pressure drop in Kitchen faucet cold water only
Author: saregister (CA)

When I run the water in my kitchen sink for a small length of time I hear a shudder from the pipes and the pressure drops. This only happens on the cold water side. If I turn the hot water on the pressure comes right back to where it was before. If I turn the cold water back on it runs normal for a second and then hammers and loses pressure again. It drops probably 30%-50% of the pressure when this happens. The longer I leave the water off, the longer it takes for the hammer and pressure drop. I've never seen this before. I haven't seen the problem in any other fixtures in the house, but I don't know if I've run any of the other fixtures that long yet. I was filling the sink last night for thawing some food and that's the first time I noticed the problem. I did the same this morning by just wasting water and it happened again.

I'm not really sure where to start diagnosing this issue. It seems like it might be a airflow issue, but I'm not sure where I could bleed any air pockets out? Could a worn/clogged aerator cause something like this? I haven't done any sort of inspection and troubleshooting yet, but am hoping for a good place to start here. Thanks!

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 Re: Pressure drop in Kitchen faucet cold water only
Author: packy (MA)

if the faucet has stems that use old fashion washers held in by screws, the screw holding the cold water washer has come loose and the washer is vibrating.
if it has cartridges rather than stems then more than likely there is debris inside somewhere.
if neither of those scenarios are the problem then the shut off under the sink has a loose washer.

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 Re: Pressure drop in Kitchen faucet cold water only
Author: North Carolina Plumber (NC)

I would suspect a loose washer in the cold supply valve under the sink.

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 Excellent! Thanks! :thumb:
Author: saregister (CA)

Excellent! I will check those washers immediately when I get home. Thanks!

Edited 1 times.

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