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I have a customer who is a large production facility with a 12-inch underground fire loop. There are 14 risers, 2 of which are 4 inch, the rest are 6 inch, with 7 fire hydrants tied in around the exterior.
The issue at hand is that they are getting false alarms on random flow switches. The head scratcher is that the water flows all test fine at around 45-50 seconds. Maintenance is saying that the risers where the alarms happened were cold (indicating water flow) and the other risers were room temperature at the time of activation. There is a 12-inch double-check backflow preventer at the water entry point. I'm starting to think about valve tampering, but I am looking for insight I may not have considered. Do you have any tips for what this might be? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
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If the fire sprinklers for an entire area or building have to be replaced, such as if they are more than 50 years old, is there any problem or benefit (hydraulically) from increasing the replacement sprinklers to the next higher K-factor (e.g., K5.6 to K8.0 or K8.0 to K11.2), especially for production and storage areas?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Forward Flow Test Confusion... I have an NFPA 13R system built in 2013 that doesn't have any hose connection(s) for forward flow testing. The sprinkler contractor is saying they're unable to conduct the test.
I am attempting to understand the codes around this topic and ran into several questions. First, NFPA 25: 2020 NFPA 25 13.7.2.3 states, "Where connections do not permit verification of the forward flow test at the minimum flow rate of system demand, tests shall be conducted at the maximum flow rate possible." Can someone please explain what this means exactly? My second question concerns using the main drain to conduct the forward flow test if it's sized appropriately. A previous Meyer Fire blog post, "Solutions for the Overlooked Forward Flow Test," Option 4, mentioned the 2016 NFPA 13 A8.16.2.4.2, but I cannot find that section in the 2019 version. Has this method changed somehow? Can the sprinkler contractor use the main drain as a means to conduct the forward flow test? If so, what else does the AHJ need to know? Calcs to prove drain size can flow system demand? Pitot reading? Thank you for reading and I'd love to find some clarity. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In NFPA 25-2017 Chapter 5 addresses "Loaded sprinklers." Of course, this has been a "LOADED" question for years and everybody's interruption of what that is whether or not NFPA gives a decent explanation of it.
My question is, we have a customer that we've performed a sprinkler test by removing an X amount of sprinklers and sending it away to a third party lab for testing which samples came back as a pass - but the question has come up asking if sprinklers remain to be loaded the same if not more over the years. What would be the timeline for re-testing? Would it follow the 10 year re-test? Or 5 Year sprinkler testing that NFPA 25 requires for sprinklers in "hazardous" environment areas? As this plant has over 600 sprinklers and getting up to them and cleaning them every year is not practical, that option is not on the table. See NFPA 25-2017 code for the discussion on it. Thanks for your take. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is an annual sprinkler inspection required for a storage room with a height of less than 12' and a room size totaling 100 square feet with a single sprinkler head installed?
I have been looking in NFPA 13 and 25 but I'm not sure I'm looking in the right direction for this ruling. Please help, thanks! Moderator's Note: So sorry crew, missed the post yesterday so following up with two today. Thanks! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What is involved in a 5 year inspection/test for a manual wet standpipe?
I see in NFPA 25, 2017 edition that manual wet standpipes are not required to be flow tested or hydrotested when part of the sprinkler system. So my question again is are there any specific requirements for 5 year testing for manual wet standpipes? Thank you all! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is a hydrostatic test required for adding two new sprinklers to an existing system?
For this, assume it can be isolated, and the local jurisdiction refers to NFPA 13 - 2016 Edition. This is the most referenced code outside of the obstruction rule, and is the most common I've seen interpreted differently amongst professionals. Reference Chapter 25, Section 25.2. What is your "threshold" for triggering a hydrostatic test? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Per 5.3.1.1.1.3, NFPA 25, 2014 Edition, states that sprinklers manufactured using fast-response elements that have been in service for 20 years shall be replaced or representative samples shall be tested and then retested at 10-year intervals."
What is the common practice for doing a 20-year sprinkler test sample on a multistory office building built 20 years ago that has undergone numerous tenant renovations, where sprinklers have been replaced and added throughout the years? My thoughts would be that maybe the common areas would have original sprinklers, but what would be the best way to approach this? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In NFPA 25 (2013), Table 13.1.1.2 directs us to the Testing requirements for Pressure-Reducing "Hose connections," with a frequency of 5 years.
Does this apply solely to 2.5-inch PRV Hose Valve outlets, or does it include the 1.5-inch PRV Hose Valve outlets on Class II (and Class III) systems as well? Can't seem to find specifics on that. Thank you. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have an instance of "flowswitch cycling" on a new wet-pipe system. The RPZ backflow is thought to be causing the flow switch to fluctuate and, therefore, not get us the flow alarm in a timely manner or at all. We have opened the manual high point air vent and flowed for several minutes with no success. Has anyone had this or found a solution to it? Potter has a technical bulletin on this but does not go into detail about how to resolve it. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  Regarding forward-flow testing, I have read that a main drain (if sized appropriately) can be used in place of other means. This was in the 2016 NFPA 13 A.8.16.2.4.2, but I cannot locate it in the 2019 version.
With that, what is the best practice for testing at the time of system acceptance? Without being able to use a hose monster, is the main drain test sufficient to ensure the backflow fully opens? Other than hydraulic calculations, how is it proven that we have an acceptable result? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA 25 states that a 3-year full flow test for a dry sprinkler system should show no significant delay in water delivery time from previous tests.
What is considered a significant delay? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We're designing a small footprint high rise with 2 stairs/standpipes, and 3" drains in the stairs for floor control valve drains and testing/verifying hose valves.
Primary water is supplied from a vertical turbine pump and tank. Local codes don’t allow direct outdoor drains so it’s either into the tank or into large hub drains. Owner is very ‘green’ and looking for ways to reduce water usage. We’ve already got the fire pump test flows back into the tank. We’re considering flowing the stair’s drains into a hub with a bypass into the tank -- hub for system draining, tank for PRV and flow switch testing. Is it advisable or preferable to run these stair drains back into the tank? Concerns include flowing black, stinky water into the tank and possibly adding pipe scale into the tank Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can any installers or maintainers provide insights into automatic air vents in fire sprinkler systems?
In your experience, do these vents ever leak water while operating? Trying to understand why specifications often require these vents to be piped to the exterior. Although manufacturers claim that only air is released, I’m curious if they occasionally sputter or drip water and whether this has caused maintenance issues. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a number of apartment buildings, 4-5 stories in height, with fire pumps serving the standpipes coming towards their end-of-life.
Is there a code requirement to re-evaluate the water supply when replacing a pump in a like-for-like scenario? Of course, this building has no existing fire protection records or placards to reference. Thanks! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I recently observed an existing drum drip assembly installed in a horizontal orientation at a low point of a dry system. Although I would never design or install a drum drip in this fashion, I do not see any specific language in NFPA 13 regarding the installation orientation of a drum drip. General knowledge and understanding tell me it must be installed vertically. The only language I can use to identify the acceptable installation orientation is manufacturer cut sheets for pre-assembled drum drip assemblies.
Has anyone come across this in the past? Would you consider this an "impairment" if conducting an NFPA 25 quarterly inspection? I look forward to hearing everyone's input. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can a company who is licensed in the installation of fire sprinkler systems perform the acceptance testing of the system or does that company need to be licensed to perform testing and inspections?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When should a red tag be issued for exterior rust on a sprinkler system?
The rust has heavy flaking especially around the weld-o-lets. NFPA 25 leaves a vague interpretation and I just need something a little more concrete to make sure we are covering ourselves. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Per NFPA 25 there needs to be a hydrostatic test of fire department connection pipe every 5 years. It does specify pipe material that are exempt (CPVC).
Should I recommend a hydrostatic test of the 2-inch FDC feed if the pipe is walled in and connected to the CPVCc before and after the check valve? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Consider a multi-story building with floor control valves (FCV) at each level.
Is a main drain test required to be performed at each of the floor control valves and tagged at startup? Is a hydraulic placard required at each floor control valve? If so, is the base of riser pressure to be the pressure at floor control valve or at the base of riser in the sprinkler riser room? Is it allowable to hang each of the floor's hydraulic placard together at the main riser in the sprinkler riser room? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When conducting main drain test on a sprinkler system with a fire pump, should the pump be on or off?
AHJ generally wants the pump to be on in this area. Thanks. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Would we still be required to conduct a forward flow test if we have a fire pump downstream and it's tested annually?
Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a unique quandary that I haven't run into before. We have an overperforming fire pump.
It was factory tested, we have a factory performance curve of 68 psi churn, 52 psi at 500 gpm (100%), and 35 psi at 750 gpm (150%). Once it was field installed, we were 1-3 psi over on Churn, 50%, and 100%, but +10 psi on the 150%. We had a net pressure of 45 psi at the 150% test when, based on the factory curve, the net should have been 35 psi. We checked the nameplate for the match, nameplate for the expected pressure at 150%; they all match. The supply for the test in the field got pretty low (about 25 psi suction at 150% flow). The only unique thing I can see about this setup is that we have a very tight room and had to meet a military spec to flow through the flowmeter and both run outside as well as back to the recirculation. As a result, the path from the pump discharge to the outside has to navigate through nine (9) elbows in order to get enough clearance upstream and downstream for the flowmeter in this very tiny pump room. Could a test header with that many bends be affecting the net pressure on the 150% test? Is this considered a failure? As this is military, it'll be by the book and I'm concerned that an overperforming pump might set up future tests for failure if I can't identify why it would be overperforming at the 150%. Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Would a dry fire suppression system be affected by freezing temperatures?
I work at a facility that had a glass sprinkler break, no contact or anything, and of course the water came out as it should. We've had freezing temps for the last few days, but where it broke was in an 74 degree room, so not frozen. Any ideas on why this would have happened? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a project and have gotten into an internal debate. The project has four diesel fire pumps in one pump house.
During testing, are we allowed to run all four at the same time? Or do we need to run each separately as we do normally to reduce the chance of blowing out a main? Anyone have insight on this? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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