Replacing 3.9k sprinklers 1

[Sprinklers89]

Have a situation where an inspector wrote up a bunch of 3.9k reliable sprinkler in a hotel that are painted. Issue is these heads are discontinued. Building owner has no records or plans or calcs for the fire system. Is there any other option then trying to do a survey (with closed walls and ceilings) and do the best we can to do a calc to prove the new sprinklers??

 

[SprinklerDesigner2]

I would remove a single sprinkler and send it to Reliable.

Sounds to me like the installation occured in the 1990's?

 

[Sprinklers89]

Why would you send one to reliable? I’ve talked to them and said because it code changes/updates the heads are obsolete and no longer made. The AHJ says since I cannot get the 3.9k sprinkler (in any make or model) then my option in his opinion is to install new 4.9k heads and re-calc the system to prove the new sprinkler still work.

 

[skdesigner]

Reliable probably has the old datasheets kicking around for the 3.9K's. If you can get ahold of the datasheet, you can see what the starting pressure and flow rates were. Senju makes a 3.7K residential pendent, that depending on the RASCO starting pressures might be close enough to call it good. Even better if it's a 13R system with 1 pendent in the entry and 1 sidewall covering the bigger part of the room.

https://www.senjusprinkler.com/product/rc-res-3-7k-ss8261/

 

[MGXFP]

Find the data sheet for the original sprinkler and compare it to available sprinklers. Pull one from the spare sprinkler box and look closely for the SIN number.

 

[Sprinklers89]

There is no comparable sprinkler everything now days is 4.9k I don’t need the sin number I know what sprinkler it is… it’s a reliable 3.9k… I needed a solution to replacing 3.9k with 4.9k without a re-calc of a building with no sprinkler plans that’s covered in sheet rock for the last 15 years.

 

[cdafd]

Have you asked the local building and fire dept, if they have plans??

Original install company in business still????

 

[Sprinklers89]

Yeah, the building dept has a floor plan but that's it. Haven't had luck finding out who the sprinkler install company was yet.

 

[MGXFP]

Per NFPA 25 5.4.1.3.2, any residential sprinkler made before 2003 can be replaced with a sprinkler +/- 5% of the K-factor. You could use a 3.7 - 4.1 K factor sprinkler. The Senju pendents above are 3.7K and Viking makes a VK480 4.0K HSW.

 

[Sprinklers89]

Yea the heads are SSP and the problem is the only Senju sprinkler I found was a concealed sprinkler these are semi-recessed.

 

[trashcanman]

Just curious, but what is your company's responsibility on this project, inspection, repair, replacement,.... or what?

 

[Sprinklers89]

We had a inspector during an annual inspection write up a bunch of painted sprinklers. We now are contracted to do the deficiency repairs. I ended up having to reverse engineer the system (to the best of my ability) to prove the new K-factors would work.