Sprinkler head in gas water heater closet?

Jells

Can anybody tell me if there's a height, placement (or any other) requirement for the head on a 40 gal tank? I found some discussion here saying it's not even required, but it seems like cheap insurance if you're doing a new install. I see that it's a good idea not to have it on a dead end. Thanks.

Zman

Is the water heater electric or gas? I would think you would want it far from the heat source and use a head with a high temp rating.

ratio

Uponor has some lit about using their product in a fire safety application, https://www.uponor.com/en-us/customer-support/faq#fire-safety.

Also, It's my understanding that a single head is classified as a "limited area system" & doesn't require any kind of monitoring—or at least, that's what I remember from about 15 years ago, so YMMV.

ChrisJ

I had looked into it a few years back and the conclusion I came up with, if memory serves, is it wasn't worth it.

I think volume of water was a concern, as well as the fun it will be if someone bumps it and breaks the glass vial. I believe it also makes a true backflow preventer a requirement as well which will need to be inspected as per the water company's rules and interval, assuming you don't already need one in your area. Unless the units in question are completely different from normal fire sprinklers, that's possible too I suppose.

After looking into it and weighing the options I decided against it for my situation.

mattmia2

Unless you are someplace where the fire department won't get there for a long time or won't have an adequate water source, probably building the partitions of the closet to have an hour or 2 fire rating would be more effective.

pecmsg

A sprinkler can do a lot of damage as well. 

hot_rod

The key with resi springs is they respond and put out the fire much quicker than fire departments can respond in many cases.

Sidewall heads, without the glass bulb are ideal, and you can cage around them also.

I just put a single head in my wood boiler room, connect to my well water source. High temperature lie flow head also.

ChrisJ

hot_rod said:

The key with resi springs is they respond and put out the fire much quicker than fire departments can respond in many cases.

Sidewall heads, without the glass bulb are ideal, and you can cage around them also.

I just put a single head in my wood boiler room, connect to my well water source. High temperature lie flow head also.

What's the gpm requirements and is a full blown inspected BFP required?

hot_rod

we used to design and install fire sprinkler systems. So technically the room size, location for spray pattern, gpm and pressure available are part of the calculation

I suppose you could add a BFD for one head?

Jells

Thanks all! Can anyone explain why a backflow is required if the head is on an active line rather than a dead end?

@hot_rod The WH is in a 24x36 closet with a louvred door for atmospheric makeup air. Seems like any minimal head is more than enough, no? I'm trying to do the right thing since it's easy enough, or am I opening a can of worms?

I found simple stuff like placing 5lb ABC extinguishers in the hallways of my multi-families to be a can of worms. I am not required to, but if I do, then I have to start screwing around getting them inspected and tested all the time! It's literally cheaper to buy new ones from Costco than get them serviced, which leads to a ecologically dubious waste stream of full extinguishers!

JUGHNE

How about CO and smoke detectors for that hallway?

Your biggest liability as a landlord is the life's of your tenant.

Also be sure there is nothing stored in with the water heater, we have all seen a cardboard box stored on the top of a water heater.

ChrisJ

Jells said:

Thanks all! Can anyone explain why a backflow is required if the head is on an active line rather than a dead end? @hot_rod The WH is in a 24x36 closet with a louvred door for atmospheric makeup air. Seems like any minimal head is more than enough, no? I'm trying to do the right thing since it's easy enough, or am I opening a can of worms? I found simple stuff like placing 5lb ABC extinguishers in the hallways of my multi-families to be a can of worms. I am not required to, but if I do, then I have to start screwing around getting them inspected and tested all the time! It's literally cheaper to buy new ones from Costco than get them serviced, which leads to a ecologically dubious waste stream of full extinguishers!

I don't know if it is....
I've just always heard sprinklers need to be isolated.  Are any of the sprinkler heads lead free and intended to be used with portable water?

I was hoping someone would chime in and say whether it's acceptable or not in the situation mentioned

JUGHNE

Every commercial fire sprinkler I have seen has maybe a 4" BFP installed....major $$.

Some systems are wet and fully pressurized...heated spaces.

Some systems are dry (cold attic) with air pressure maintained to hold back water until needed.

Some have glycol portions or glycol head that stick outside or into walk in freezers.

But the dormant water inside the piping (usually black) is some of the nastiest crap you might ever see. Think of the worst boiler water possible.

The only flushing done is when a flow test preformed by opening a valve inside the building. The crappy stains down the outside on the brick shows.

Then there is a fire dept. connection. Usually Siamese 2 1/2" female connections outside the building connected to the sprinkler system.
No valves outside, just check valve inside the building that fire truck can overcome.

This is for fire pump engine to increase the pressure and you may never know where the water is coming from for this input. Ditch, river, lake, swimming pool etc.
Usually from the same main (fire hydrant) that the building is connected to.....advantage is that you can double or triple the system pressure.

The 4" water supply coming into the building also feeds the domestic water so you definitely want isolation of the 2 systems.

All that being said, I did add a sprinkler head into the broom closet of a small schoolhouse. Had to be 1" iron pipe or silver soldered copper, IIRC I went for the copper. It was connected to the CW in the boiler room which BTY did not have a sprinkler head at all. Closet had the only head. No BFP required.

Also installed fire alarm in system at that time.

It made the AHJ happy.....if he is happy then all is good.

Jells

JUGHNE said:

How about CO and smoke detectors for that hallway?
.

Yes, smokes are required by the state on every floor and in the vestibule, as well as CO and smoke detectors in the units. No CO required in common spaces, nor even the utility room.

Jells

Thanks @JUGHNE. Years ago heating guys installed a sprinkler in one of these WH closets as part of the work, and it seemed like a great idea. Maybe it wasn't. But the head was on an active feed line, not a dead end. I'd have to see if there's lead free heads even available.

JUGHNE

There are/were residential systems, 13R ??, that use the domestic water lines in the building so I would imagine there are LF heads available for those.

IDK, you might want a higher temp than usual for that closet.

mattmia2

The code says something like parts of the system carrying water for human consumption so there is an argument to be made that sprinkler piping and hose bibs and maybe even hot water piping are not required to be lead free.

but stagnant water is an issue. i know I saw some heads that were flow through at some point to prevent them from being a dead end of the system.

JUGHNE

In a full commercial system there are dead ends all over.

I think the concern for residential domestic is to not have a dead end to a sprinkler that is connected to the potable water.
Just as any abandoned branch of some length should be disconnected from the CW system.

I believe it is thought that with water flow and pressure changes the dead end stagnant water could get pulled into the active portion of the piping.

Think Legionnaires Disease.

Larry Weingarten

Hi, Uponor has this: https://www.pmengineer.com/articles/94271-uponor-fire-sprinkler-system

Yours, Larry

hot_rod

Uponor has been selling the AquaSafe combined plumbing/ sprinkler for years, they must have NSF listed heads?

hot_rod

Either connect it as a flow though line, or add a Venturi fitting that establishes some flow in dead legs. Kemper or some German company has a fitting to add to dead legs on DHW piping to keep some flow movement. I thought Viega had a fitting also?
I suppose a simple check valve would be enough to keep me from lying sleepless worried about 1 short run. Not much different from an unused. bathroom  group in a home or hotel

It depends on your comfort level and if a fire or Legionella will get you😙

mattmia2

JUGHNE said:

In a full commercial system there are dead ends all over.

But they also have an rpz backflow preventer, right?

rick in Alaska

I was a sprinkler installer for 6 years, about 30 years ago, and did mostly residential. I would have no problem installing a single head in your closet. I would put it on a "through line" and not worry about a check valve or backflow. I would get a head that is compatible with using a head protector if it looks like it could get hit by anything, or just be careful around it. They are pretty tough and you would have to hit them pretty dang hard to get them to go off.
NFPA allows a minimal amount of heads in a 13R code situation like you are doing, and if you wanted to do a whole house job then you would be looking at 13D code requirement. The requirement for a backflow is going to be totally dependent on if you are on city water, and if you have inspectors. In Portland, the houses we did were all protected by a 1" RPZ device.
Bottom line: Do it.
Rick

PC7060

As a FYI, in Virginia, the code requirement for sprinkler systems in residential buildings was waived as part of the state code variance initially implemented in 2009 and again in 2019.
However if you put even so much as one head in your house the AHI will (can?) require the entire property has to be brought up to full compliance.

Be a good idea to talk to your code authority first.