Madison Heights, MI · Member since 2014 · 471 posts · 132 votes
I am remodeling a kitchen in one of my rentals. I cut one of the water shutoffs for the kitchen sink, because it has a slow leak. I bought both a push fitting and a compression shutoff, but both were just slightly too small for the tubing. The 5/8 od is too small, and the 7/8 is too large. The OD of the copper pipe is 3/4.. It looks like they used refrigeration tubing for the water supply.
I either need a shutoff that will fit directly onto 3/4 OD copper, or a fitting to convert from the 3/4 OD to the standard 5/8 OD for 1/2 copper plumbing. I'd rather not replace the whole service, because I would either have to cut out the floors or dig in the crawlspace to access the plumbing. Any ideas??
Williamsville, NY · Member since 2015 · 80 posts · 34 votes
9y
@Wilson Churchill, the only difference between refrigeration tubing and plumbing tubing is the way the pipe is listed in sizing, refrigeration tubing is measured in OD and plumbing is measured in ID so your standard 3/4" plumbing tubing is 7/8" refrigeration tubing. it is literally the same pipe just listed different. So what you are saying is 3/4" OD would be a 5/8" plumbing fitting. you may have to find a local plumbing supply house for a 5/8" shut off.
You could try using the fitting that's a slightly too small, use your tube cutter to crimp it down, then soft-solder it to seal the joint. Not right, but could work.
... or, get one that's a touch too big, get the right tool and swage the supply line out to make the shutoff fit.
... or, use the size conversions Michael Karl suggested to find the right piece to make the connection. May need a reducer to mate up the shutoff to the supply line.
@Wilson Churchill, the only difference between refrigeration tubing and plumbing tubing is the way the pipe is listed in sizing, refrigeration tubing is measured in OD and plumbing is measured in ID so your standard 3/4" plumbing tubing is 7/8" refrigeration tubing. it is literally the same pipe just listed different. So what you are saying is 3/4" OD would be a 5/8" plumbing fitting. you may have to find a local plumbing supply house for a 5/8" shut off.
Actually, the ODs are different. 5/8 fitting was too small, 7/8 was too big. The good news is that I found a refrigeration supply place that had a coupling to connect the two. Problem solved.. It only took a day of calling and driving around to find one coupling. Grrr
One of the customers explained that I could have also used a swaging tool to make one pipe fit into the other and solder it.