Shouldn't Sprinkler Leak Show in Hydro. Test?

12/6/2021

We had an insured account suffer a sprinkler leakage loss when the sprinkler system was charged with water and a sprinkler leaked.

Wouldn't the above-ground hydrostatic test have discovered this?

I know the hydrostatic test is intended to discover leaks in pipes but shouldn't it also identify leaking sprinklers?

The general contractor and sprinkler contractor are having to replace multiple thousands of sprinklers in these buildings. I appreciate your input!

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16 Comments

Fred

12/6/2021 06:01:43 am

NFPA 13 allows hydrostatic testing with sprinklers in or out. Possible that system was a tested with plugs instead of sprinklers.

Anthony

12/6/2021 07:50:15 am

Only pendant and side wall head outlets can be plugged and tested. However Its bad practice to not at least run an air test on the system after heads have been installed. If for no other reason than to ensure you didn't miss a head during install. That MIGHT have helped avoid this problem.

Why are they replacing thousands of heads? Shouldn't only the leaking heads be replaced?

Make sure you contact the manufacturer to ensure they didn't have a recall.

Also Might want to check that the heads were not defective upon delivery to the installing contractor. Maybe an independent analysis from a consulting quality engineer?

Dan Wilder

12/6/2021 07:52:12 am

There is a lot of info needed to make a better reply.

Was the system (or the leak location more specifically) new, under a TI that required a hydro, or existing and under a 25 inspection?
What level was the leak - Drops up to a full blow out?
Where was the leak - At the thread/fitting interface? From the seat of the sprinkler?
Was the leak from the fitting (pipe/fitting) instead of the sprinkler/fitting?

The Hydrostatic test (like any other test) can confirm continuity a the time of the test and is a good indicator of a complete system however I have had dry fit CPVC fittings, grooved couplings not tightened down, welds and threaded fittings leak pass a hydro then, then at some later date break/leak/blow apart.

Unless there is a valid reason to change out all the sprinklers (older sprinklers under voluntary recall perhaps?), changing out all of the sprinklers seems excessive (again, missing some info).

I'm not looking to call out a MFG, but have there been conversations with the installing contractor and the sprinkler MFG?

Glenn Berger

12/6/2021 08:11:57 am

Simple answer to the original question.

A hydrostatic test, if done correctly, would have failed if there was a leak in the system.

The question that other commenters mentioned: When was the hydrostatic test completed? If there was a leakage in the system, then where are the flow alarms?

Jesse

12/6/2021 08:18:33 am

A lot of variables here.

The hydro is to test the piping primarily. Often, some pendents are yet to be installed at the time of the hydro, so if that's the case the pendent wouldn't have been subjected to the test. If it were installed, and leaked at the time of the hydro, the hydro would have failed.

If there was a subsequent finish-out after the hydro, there would not have been a second hydro if the modification was small enough, but rather a test at operating pressure.

Finally, there is the possibility that the sprinkler did in fact just fail. This is pretty rare, but it has happened.

Alex link

12/6/2021 08:47:45 am

A lot of good comments above.

To second everyone, to provide a more detailed response, we would need more information. Since the test can be done with plugs, it’s possible that it didn’t show. Although, always request an air test with all heads. That way you ensure your entire system is sound.

I’m also curious why you have thousands of heads to replace?

Hope the situation pans out.
Alex

Greg

12/6/2021 08:57:10 am

A root cause investigation is needed. As in many of the replies above, various factors appear plausible but there should be a narrowing of these to accurately determine cause.

Construction projects move quickly and small decisions can change an outcome. Working through a detailed analysis will help to arrive at a plausible conclusion. A single action or independent actions that aligned will present as the reasonable cause.

Brad K

12/6/2021 10:05:10 am

I for one would appreciate a code reference for hydrostatic testing with plugs mentioned above. I myself do not recognize hydrostatic testing without the sprinkler installed as one certifying a system by state statute. NFPA 13 & 25 defines a hydrostatic test on pipe with attached appurtenances. I would consider the sprinkler an attachment. Even an act of adjusting more than 20 sprinklers requires a new hydrostatic test per NFPA 25 5.5.1.

Brad K

12/6/2021 10:11:29 am

Sorry Greg.
I mistakenly clicked the wrong reply button.

12/9/2021 10:18:15 am

Agreed.

Steve monroe

12/12/2021 01:36:11 pm

30 yrs in sprinkler trade.I would have to say a hydro test without the heads installed is not a solid point of the final outcome of the hydro in the first place.
Why double the time of the final outcome?.
Who is installing this job?.

Mike

12/6/2021 09:44:26 am

I've had leaks from manufacturing defects the manufacturer withheld until after we complained about them.

These were found during the hydro.

I'm not sure how large your leak was and the manufacturer needs to be involved.

I'd save all the heads.

It doesn't seem plausible all heads would have leaked. Could have been caused by mechanical damage by a fitter or another tradesman.

Jack G

12/6/2021 11:57:07 am

Always hydro with heads installed.
If thousands of heads are leaking, it sounds like a problem that occurred years ago(30 or so ). When the manufacturer puts a thread on the sprinkler, sometimes there is a microscopic layer of metal dust. If you Teflon over or dope over, days later leaks occur. A major supplier paid out dearly.
With a lot of the heads being made overseas, the problem could of occurred again.

sean

12/6/2021 12:24:33 pm

something really went wrong with this. I don't see how replacing tons of heads could not have been caught during any of the pre-testing.

Who witnessed the hydro?

Dan Wilder

12/6/2021 01:20:32 pm

Testing with plugs:

NFPA 13 - 2019
28.2.1.8* - Allowable with pendents & horizontal sidewalls or plugs.

*Appendix says a second test "should not" require an additional hydrostatic test.

Not advisable but understandable with varying construction elevation tolerances and where the actual ceiling is measured from (slab, FF, top of floor overlayment)

Donnie

8/22/2023 07:48:11 pm

Can a pressure washer cause enough damage to upright QR glass bulb sprinkler heads that would cause an activation of a dry system. 6 heads were found to be fused on a dry pipe system that was being placed back into service?

Shouldn't Sprinkler Leak Show in Hydro. Test?

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