alternative to heat tracing fire sprinkler pipes...

[deltasprk]

....I have a bit of a dilema here. I work for a fire sprinkler contractor and we are having to provide some sort of heat conductive properties to the fire sprinkler system to prevent freezing. We proposed using armaflex insulation but that was rejected by the A.H.J. We are having to use some sort of heat tracing or an equivalent. The problem is that a power supply will have to be supplied and the building owner is trying to avoid that. Is there any other sort of method of preventing lines from freezing without using heat tracing ? How about an insertion device that increases the temperature of the water in the system should the temperature drop below a certain temperature ? Is there an "outside of the box" idea ? Any help would be appreciated. Thanks.

 

[SprinklerDesigner2]

I've never heard of anything but I will watch this thread.

 

[LCREP]

U have 3 choices based on NFPA 13

"We proposed using armaflex insulation but that was rejected by the A.H.J."

1.Dry Pipe Valve
2. Antifreeze system
3. Heat trace tape Listed for fire protection, insulated coverings, frostproof casing or reliable means ( what ever that is!) See NFPA 13. 07 sec 8.16.4.1.3

Based on 3 above I would ask the AHJ why not and point to this code section. This may be a new thing in the 2007 edition, so u may be out of luck.


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Fire Sprinklers Save Firefighters’ Lives Too

Not ALL Sprinkler Systems Are Created Equal! An Inadequate Sprinkler Design Is JUST As Bad As A Nonsprinklered Building!! When Occupancies Change So Should The Sprinkler System. See NFPA 25, 2002, Edition, Section 4.1.5, 4.1.6 & 4.1.6.1.

 

[TravisMack]

With heat tape, you are not allowed to use it on branch lines, if I remember correctly. Other than that, LCREP is on the ball with your options.

I have never heard of anyone using just insulation without heat tracing. If you don't want a power supply, it sounds like you are going the anti-freeze route. A dry system would need a power supply for the compressor.

Good luck!

Travis Mack
MFP Design, LLC

 

[deltasprk]

Thanks for the reply's so far everybody! I failed to mention that this is for a standpipe ONLY in an open stairwell. That is what is making this so hard. Thanks and keep em' coming'.

 

[TravisMack]

How tall is the building. If it is less than 75', you can do a manual dry standpipe. then, you have no concerns.



Travis Mack
MFP Design, LLC

 

[ChrisConley]

Depending on the number of heads I would highly recommend a glycol system. It can be added to just the area(s) of concern.

We frequently specify them near large overhead doors.

Nothing wrong with dry pipe, but dry pipes tend to corrode over time.

 

[firepe]

I agree with Travis,

UNLESS you have also managed to try to feed sprinklers from said standpipe, then you DO have CONCERNS.

Are there any other pertinent details that have been left out so far?

 

[deltasprk]

We proposed a dry manual standpipe but the A.H.J. came back and wants only a wet automatic standpipe. It seems as though every possible solution gets shot down. I'am thinking about using an antifreeze loop in the standpipe since the standpipe is only a hose valve standpipe and is not used as a dual feed (I.E.-feeding hose valves and floor control assemblies).

 

[TravisMack]

A dry manual standpipe should be allowed. But, it sounds like you have lost that battle. I would then just put in an anti-freeze system. It solves the problem of not wanting a power supply for the site. But, you may need to put in a RPZ backflow preventer because of the anti-freeze solution. You would need to check with the water authority on this. Also, if this is an automatic standpipe, then you will need a pump unless you have really good water pressures. How are you providing 100 PSI at the top outlet with city pressure only? And, if you are able to make it on city pressure, will the additional of the RPZ losses prevent you from getting the 100 psi at the top outlet?

Travis Mack
MFP Design, LLC

 

[stookeyfpe]

Be careful on the manual standpipe. IFC Section 905.3.1 requires a Class III standpipe if your building is more than 30 feet above the lowest level of fire department access, unless the building is an open parking garage.

 

[deltasprk]

We indeed do have a pump and as such only a manual wet standpipe would work w/o a pump since you could consider the pumper on the fire truck as a pump that would hook onto the FDC. Having an RPZ would only knock off about 7-8 PSI from the safety margin so it shouldn't be a problem. This has been one of the all time "thinkers" that I have ever encountered. I cannot reveal what company I am with, what project this is for, or what jurisdiction I am working in but I will reveal it is the State of Florida and in the State of Florida the code is sometimes whatever the fire marhsall, City Engineer, or other powers that be state it is, NFPA be damned!

 

[Cidona]

It seems that if you have a pump you need power. Even if it's a diesel pump you'll have supervisory power requirements. Is it that the owner doesn't want a big electric bill every month to trace heat? Somebodys paying to keep the pump room warm. If he is ok with the supervisory power demands, you might do a automatic dry (with bottles/compressor). I know you said the AHJ wanted a wet automatic, but sounds like somethings going to have to give here. Either AHJ or owner.

 

[TravisMack]

I have designed projects in FL and I know exactly what you mean. No need to say any more

Travis Mack
MFP Design, LLC