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
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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 Does the requirement under NFPA 25, Chapter 14 for a 5-year internal pipe inspection apply if the system is an open sprinkler/nozzle deluge system?
The system is flowed annually and I believe that this full flow should meet the requirement in lieu of a 5-year internal pipe inspection. Am I correct? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe For the acceptance testing of a dry pipe sprinkler system, is a 24-hour 40 psi pneumatic test required, or will the 200 psi hydrostatic test alone suffice?
Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe A fire department connection can be used with a bypass to facilitate a forward flow test of the backflow preventer as described in NFPA 25 Annex A.
Is there anything prohibiting the FDC from being used as a drain outlet, as well? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What would cause a 10% reduction in the full flow residual pressure from the current main drain test, when compared to the original acceptance test or previously performed tests?
If the original acceptance test or previously performed test information is not available, then the residual pressure on the current main drain test must be within 5 PSI of the design/demand pressure. What would cause a decrease over time? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can an auxiliary drain for a dry system be mounted on the side of pipe?
We've debated it recently after finding a situation where the auxiliary drains were mounted on the side of the pipe. I've been unable to find proper documentation concerning the orientation for the auxiliary drain. I did find the 5-gallon rule for wet systems, however, I was unable to find a specific reference for a dry system. Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have observed forward-flow tests of backflow preventers, and fire pumps tests, that are conducted through 2.5-inch nozzles identical to the image below, but without the playpipe tip screwed onto the end of the nozzle.
Image Link The pitot reading was taken off the 1-3/4" threaded end of the nozzle where the playpipe tip gets screwed on. Is this approach acceptable, and would the GPM table for the 1-3/4" butt for converting the pitot pressure to flow be acceptable? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a project in Geelong, Australia, where the product that is bulk-stored within the building makes for an extremely dusty environment when it is unleaded.
Sprinkler protection is proposed to protect the building - but I wanted to ask the question about "excessive loading of sprinklers". What's the best option to minimize the loading on the sprinkler? NFPA 25 mentions this, of course, but our code in Australia does not mention this term but does state that the sprinklers need to be visually checked annually, and suggests that a more stringent maintenance routine be in place for these environments. The bulk product is phosphate rock and it typically used for the fertilizer manufacturing plant across the road. Any suggestions would be much appreciated. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I got asked a weird question about NFPA 13 requiring sprinklers to be readily accessible.
A co-worker told me they didn't believe some sprinklers that would installed in a mechanical room we're designing would be easily accessible post-construction and asked if there were any kind of access requirements. I can't think of anything in NFPA 13 that would require every head be easily accessible in the same way that NFPA 72 requires certain fire alarm components to be readily accessible. Is there a requirement that sprinklers be accessible? Where does this stem from? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe How do I, as an AHJ, address contractor scope limitations?
Project where an installer presents plans to replace 328 sprinklers and is changing some pipes out. Many times the installer says they're only responsible for pipe from the riser - not for a hydrant flow tests. What is the best way to navigate this to be sure that there's still sufficient water available? It could be a one-for-one replacement, but what if there's significant work being done - what code basis is there to make sure than an effectively-new system can work with today's water supply? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a remodel project with XL pipe and push fit fittings. When there is a leak in the fit fitting what product or method can be used to change the pipe to schedule 10 with grooved fittings? Can XL be grooved? Is a roustabout approved for XL? There is virtually no information on the internet regarding XL except for notable failures with the material. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am running into a lot of old systems that do not have hydraulic placard and some of them are old Pipe Schedule system.
Has anyone ran into an old pipe schedule system were the fire marshal is requesting hydraulic placards and if so has anyone found a way to satisfy the requirements without surveying the entire system and running new calculations? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Does an FDC have to be hydrostatically tested every five years?
Is that commonly done as part of a 5-year test? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Our condo units are 23 years old. A recent inspection of the sprinklers had some rust on the exterior of the pipes near the sprinklers.
Can we wire brush these areas and spray with a rust inhibitor, or do we need to replace all those pipes? Are other inspections needed to see if any rust is inside the pipes or how thick the pipe steel remains? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe During fire pump testing, for the churn test, should the system valve (on discharge side of course) be open or closed?
I lean towards it being open, as I would rather know the weak point during a test than during an actual fire event. Here's my pro/con list to keeping the valve open: Pros (keeping valve open)
Cons (keeping it open)
Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What is the proper point in a system to take the antifreeze sample?
I have taken readings at both outlets at the check valve, unfortunately a contractor is saying to take it at the most remote point. Those locations are either 25-feet in the air, or not installed at all. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Section 5.3.2.1 of NFPA 25, Gauges shall be replaced or tested every five years by comparison with a calibrated gauge.
Is it required for us to provide a sticker on the gauge to indicate it has been re-calibrated by the 3rd party, or will a sharpie inscription on the glass of the gauge be sufficient to meet this requirement? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In the introduction (Origin and Development) to the 2023 Ed. of NFPA 25, it mentions that several changes have been made to Chapter 5, "such as additional requirements to remove concealed sprinkler cover plates and inspect the sprinklers". I have scoured the text of Chapter 5, and cannot find this requirement anywhere.
Was this discussed but not implemented? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is missing a coverplate for a concealed sprinkler a deficiency in NFPA 25 that would be required to be corrected?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When testing our flow switch, the first time, it will take 25 seconds before the flow switch activates. When we reset and start over, it takes 5 seconds for the switch to activate.
After waiting an hour to test again, the first test always takes 25 seconds for the switch to activate. Any thoughts on why? This is running on an 8-inch pipe. The flow switch on all of the 6-inch pipes work properly. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Hi All, Is there a code reference on the maximum amount of time allowed to close a wall PIV (or any valve for that matter)?
I have a Wall PIV that is hard and slow to turn, and takes about 30 minutes of fighting to fully close. Servicing of accessible components has not helped. I probably won't be able to get funds to repair/replace unless I can quote a code violation. I have only found a minimum amount of time, but nothing for a maximum. Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe While doing a sprinkler inspection it was found that the main check valve for the system failed. The system was installed before backflows were mandated on sprinkler systems.
I know that a backflow preventer needs to be installed in its place, but have been unable to find any code that says it does. Anyone able to help? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What is the best procedure to use when testing a 3,500 gallon diesel fire pump that is equipped with a throttling/pressure governor installed on it?
My graph was well below the rated curve at 50% and 100%, but the governor seemed to disengage at 150% flow and my numbers exceeded the rated curve when we pushed this much water. I did not attempt to change the controller settings or unplug the device (if that's even possible) to disengage the forced idle at 50% or 100% but insurance isn't "buying" that the pump didn't fail. These pumps aren't more than 5 years old and are ran on a tight schedule once a week (by the way). Maintenance thinks it'll lead to faster wear and tear on the motor and I agree. All I could really do was state the facts and hope I don't have to go back out there and do the test again. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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