Sprinkler system leak

The following information was provided by Duane Damiano on SW Windwood Way.  At the end of the post, there is a link with photos of the pipes in question.


On Saturday, May 13 we noticed a small bulge in the ceiling adjacent to the fire sprinkler in our master bedroom.  I immediately went into the attic and discovered that a plastic pipe fitting attached to that sprinkler was leaking.

I place a pan under leak and collected approximately 6 ounces of water per day for next three days.

On May 16th, I shut off the main water valve in garage and released the water pressure by opening a kitchen faucet. I turned the water back on after a few minutes.  The pipe no longer leaked.

On June 2nd there was still no water leakage.  My plumber (Kenny from Lovett Plumbing) inspected the pipe.  We agree that the best course of action is to do nothing.  I will monitor the situation and call Kenny if it starts leaking again.

* Cause of the Leak

The cause is unknown.  One possibility is that shutting off the water and releasing the water pressure on May 16 caused the AquaPEX pipe to re-shrink around the fitting.  As bogus as that explanation sounds, it’s been offered by three people – two plumbers and one knowledgeable friend.  I don’t buy it, but I don’t have a better idea.

A couple of people have suggested that the ‘leak’ could have been water coming through the roof and dripping on that spot.  I think that’s unlikely for the following reasons.

1. The leak was discovered on Saturday, May 13.  It rained, by similar amounts (about 0.08″ per day) every day from May 11 through May 17.  The leak stopped on May 16 and the time of stoppage is exactly coincident with the time that I briefly shut off the water valve.

2. The sprinkler head was covered with blown in insulation, which I had to push aside.  The insulation above the sprinkler was dry.  The only wet insulation was below where the pipe attaches to the sprinkler head.  The ceiling material below the pipe was also wet, as can be seen in the first photo.

3. If you look closely at the foil pan in the second photograph, you can see a couple of drops of water in the pan, under the pipe.  I took that photo shortly after putting the pan in place.  I could see drops falling into the pan.  I didn’t measure the frequency, but it was a drop every 20 seconds or so.  It seemed obvious to me at the time that it was coming from the pipe.

* Things You Should Know When This Happens to You

I spent a lot of time phoning and emailing sprinkler and plumbing companies.  Almost all that time was wasted.  Here are the key points.

The AquaPEX pipe used in our sprinkler systems is made by Uponor.  Here is a video that describes the system.


This is the Uponor “Find an Installer” web page.


When you fill out the form, don’t forget to select “Fire Safety Systems” from the choices at the bottom.  If you do this now, it will return only one installer, Wolcott Plumbing in Troutdale.  When I called them, a woman named Gloria told me that I lived too far away for them to send a service truck.  She suggested Ed Mullan Plumbing and Gravity Plumbing.  Ed Mullan is in Hillsboro, but he does not do any repairs except on systems that he has installed.  Gravity is in Oregon City (almost as far away as Troutdale).  The Gravity guy said he could do it, but he was many weeks backlogged with work.

Don’t be discouraged.  When your turn comes, maybe the Uponor site will offer more choices.

I finally found Kenny, who works for Lovett Plumbing (503-737-8423, lovettservices.com).  He knows about AquaPEX pipe, and he carries the pipe and fittings in his truck.

* Want to Fix It Yourself?

I’d think very hard about that.  You’ll need the expander tool, which costs about $400 or can be rented for $40 per day.  If you watched the video, you saw how easy it is to use the tool to attach the pipe to a fitting.   However, the video does not demonstrate how to remove pipe from a fitting.  The accepted way to do that is to heat the ring and cut through it with a knife.  After removing the ring, heat the pipe some more until it slides off of the fitting.  Not too hard, but what if the fitting is a sprinkler head that is designed to spring open at 135 F?  Do you want to point your heat gun at that?  Kenny from Lovett Plumbing says he can remove the pipe without heating it.  I hope so.


An updated album of photos, with captions, is here:


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