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Vacuum Pump to Drain Sprinkler Line???

Vacuum Pump to Drain Sprinkler Line???

Vacuum Pump to Drain Sprinkler Line???

(OP)
I have a fire protection sprinkler line above a finished space that needs significant modification.  The mains are no problem to drain; however, each drop down to the heads is about 6' long.  Those drops will not drain until the heads are removed, thereby making a mess all over my office space.  We will of course put down tarps, buckets, etc. but I would like to get all of the water out before breaking the line.

There is a liquid ring vacuum pump on site.  Can it be used to suck out the water?  If so, how would this be done?  Would I need to put in a tank between the pump and the sprinklers to catch the water as it is coming back?  Any ideas?  

RE: Vacuum Pump to Drain Sprinkler Line???

You want be able to use the vacuum to remove the water from the head drops unless you put a vacuum hose down each drop.

The way I've seen this handled is to unscrew the branch connections at the headers, far less water.  I've also seen just removing the heads as you state  and not causing too much mess.

Either way you do this make sure you have some replacement pipe and few heads on hand.  

RE: Vacuum Pump to Drain Sprinkler Line???

Pollard Water supplies a series of pumps (see e.g. cigarette-lighter powered one at http://www.pollardwater.com/emarket/pages/littlegulp.asp) designed to pump out hydrant standpipes etc. -- ideas that could conceivably help you.    

RE: Vacuum Pump to Drain Sprinkler Line???

I don't know where your project is, but in Texas, NO ONE can legally do ANY modifications to a sprinkler system except a licensed sprinkler contractor.  This includes draining of the lines.  Better check with your local Authority having jurisdiction before doing anything with the sprinkler system.

RE: Vacuum Pump to Drain Sprinkler Line???

Follow up:  The exception of course is for a Fed. bldg., or some entity not under local jurisdiction by the Fire Dept.

RE: Vacuum Pump to Drain Sprinkler Line???

when we drain the water out of log drops in finished areas and can not make a mess heres our trick. first loosen the head until it is just hand tight-take a garbage bag and cut the bottom out of it-slide one of the open ends of the bag up over the drop several inches and secure it with duct tape- place the other end in a five gallon bucket- now unscrew the sprinkler head that is inside of the garbage bag and let it fall into the bucket-the bag acts like a funnel and there is no splash. if there is more than a five gallon bucket full just put your thumb over the end of the bell reducer that is still inside of the bag and have your helper trade out with another bucket.

works every time.

hope you are a sprinkler contractor because you are dealing with a life safety system not just the plumbing!!!

G3

RE: Vacuum Pump to Drain Sprinkler Line???

(OP)
Thanks for your replies.  I'm a mechanical contractor, but a licensed sprinkler contractor will be making the changes.  The end-user has a vacuum system and came up with the idea.  I still would like to pursue it.  Can I put a tank in line to catch the water?  Will it even work while the system is closed, or would we have to remove a head to allow air to rush in and sweep the water back with it?  I don't have much vacuum experiance.

RE: Vacuum Pump to Drain Sprinkler Line???

just use a shop vac onn a drain valve that is close to the heads. duct tape it on and then loosen up the head, it will suck the water up enough to get a bucket under. try the trash bag trick...........trust me it works.

G3

RE: Vacuum Pump to Drain Sprinkler Line???

If you insist in wanting to use a vacuum pump to drain the drop legs you will need to allow air to enter at the sprinklers so as flow can take place - Plus you need to recap each drop leg after it is drained so as to re-create a vacuum in the system for each drop leg. The alternative is that you  will have to create an extremely high vacuum, high enough to vapourise the water from the system and then you will probably not remove all of it anyway.

So, seem you back to letting in some air at the sprinklers with complications  - no better a method than the method pipedream suggested.   

Having a vacuum pump on-site and a suggestion of the end-user is not an imperative that it is done that way.

Naresuan University
Phitsanulok
Thailand

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