How to cap a copper refrigerator water line without a shutoff valve
To cap an active copper water line that lacks a shutoff valve, you must first shut off the main water supply to the house to prevent leaks. You will then need to identify the specific type of connection—such as a piercing valve or compression fitting—and use the appropriate compression cap or plug to seal the end securely before turning the water back on.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Shutting off the main house water supply
- 2Installing a cap on the open copper line
- 3Calling a professional plumber to handle unfamiliar or copper fittings.
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“The copper line has not shut off switch or valve. I had to shut off the entire house water for us to be able to prevent a water leak from the copper.”source ↗
“Can I just put a cap to the copper line? If I put a cap that stops the water from flowing thru the end, will it lead to an issue?”source ↗
“I just moved it to get behind it and clean up and now the line behind it leading to our water heater is leaking and with my minimal plumbing experience I have no idea how to remove this and cap it.”source ↗
“It appears to be pierced into the line in a way that I've never seen before. Does anyone know what parts I'll need to close this up?”source ↗
Where this came up
People with this problem also raised
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