Dry Heads on Freezer/Coolers

[NJ1]

I once heard that the length of dry sprinkler heads to be selected on freezer/coolers is based on how cold the inside will be. That comment seems a bit confusing since I do not see any relevance to temperature as long as you insulate the sprinkler head properly.
I just got a job to install 135 dry sprinkler heads in new freezers. The installation calls for exterior overhead piping and drop down pendent heads.
My question is: Would I be able to use 6" adjustable dry heads on this application dropping 1" pipe, then tee and then dry head

 

[skdesigner]

NFPA 13 2010 8.4.9.1 Where dry sprinklers are connected to wet sprinkler systems protecting areas subject to freezing temperatures, the minimum length between the sprinkler and the fitting shall be in accordance with the manufacturer's instructions.

8.4.9.2 Where dry sprinklers are connected to wet pipe systems protecting insulated freezer structures, the clearance space around the sprinkler barrel shall be sealed.


page 8 of this site shows Vic's required clearances. Should get you started.

http://www.victaulic.com/Docs/lit/40.61.pdf

 

[NJ1]

This is good I just learned something new for the reason why the national standard size used is 12" so you dont ever get to learned this things often.
It is basically a manufacturer requirement and not NFPA requirement

 

[FFP1]

Reliable Model Dry Pendent Requirements:

General Installation Instructions
Model F3QR dry sprinklers must be installed only in standard (ANSI B 16.3 class 150 and ANSI B 16.4 class 125) pipe tees in the horizontal position, even at branch line ends. They should not be installed into elbows or pipe couplings located on drop nipples to the sprinklers.

NFPA states dry pendents shall be installed in accordance with the manufacturer's installation guidelines.

Good Luck with the project.......the best method is to use dry pendents fed directly from the tees in the horizontal branch lines.

 

[NJ1]

I got it. Thanks

 

[cdafd]

I am trying to learn

What is a """6" adjustable dry heads""


Do you have a web link to one????

 

[NJ1]

As you can see the sleeve and skirt sprinkler head has and adjustment up and down of about 2-3 inches.
Thats why is called adjustable.

 

[fireguy519345]

I seem to remember that Tyco requires 12 inchs of the drop/upright to be in a warm area.

The reason the dry head is to screwed into a tee, not a 90°,is the clearance inside the fittings. Hold a dry head next to a tee and a 90°, and you can see the difference. Having a tee with a plug also makes obstruction testing easier.