Re: Ever done this?

["Frank Olson" <Please-use-the-email-links@xxxxxxxxxxxxxxxxxxxxxx>]

"JoeRaisin" <joeraisin@xxxxxxxxxxx> wrote in message
news:dYP1f.1661$dO5.81@xxxxxxxxxxx
> So this is how my day went....
>
> Installing a Vista 32-FB in a county building to monitor hte sprinkler
> system (they have both wet and dry systems)
> Got flex to all the flow and tamper boxes except one and am working on the
> last...
> First step, knock out the knock out on the back of the box - careful of
> the 110 bell circuit already wired to one of the switches.
> Put my punch on the perimeter of the knock out and tap with my
> hammer...nothing...
> Second tap and the box breaks off, the bell starts ringing and air shoots
> out of whats left of the pipe (it was the low air alarm)
> I put my finger over the hole to keep whats left of the air pressure (now
> at just over 30 lbs) in the system until I can get the water shut off
> (lesson learned there - shut it off FIRST)
> The water valve is chained and no key in sight.  Bell ringing right over
> my head but nobody seems to notice.  For at least 5 minutes I am standing
> there under a ringing bell with my finger blocking the hole.  I figure If
> the clapper releases I will then have water shooting out of a 1/4 inch
> hole with a lot more pressure than the air currently is.
> Finally someone notices me and I send them looking for the key to the
> chain holding the butterfly valve open.
> No key can be found and it takes several more minutes before bolt cutters
> can be found to cut the chain and shut off the water.
> The sprinkler guys show up later and replace the switch.  The fella I
> spoke with said he has never seen one do that before, but theyt have
> recently started using plastic fittings to connect the tamper boxes to the
> pipes.  (Plastic pipe, 3/4 od and 1/4 id)
> We tapped out both knockouts BEFORE mounting the box this time....
>
> Question: Anyone got a better way of getting rid of those knockouts?  I
> thought of a 7/8 hole saw next time but not sure how well that may work
> since they tend to get grabby and either twist off the box or slam my
> drill (and hand) into something delicate or energized.
>
> I would rather not go through this again....
>
> BTW, I later found the key in the spinkler repair parts box next to the
> wet risers on the other side of the building (which is the first place I
> told them to look)


There's never an "easy" way, is there?  Plastic pipe on a dry valve for a
sprinkler system??  Not here!  You'll see "blaze pipe" all over the place in
most wet systems, but I've never seen it on a dry (which is mostly located
in parkades and unheated out buildings) and *never* on any valve components
(wet, deluge or dry).  I do know the knockouts on some flow switches and
other sprinkler devices can be a pain.  I use an ice pick.  I line it up
with an edge of the knockout, not the centre.  Once a bit of it is lifted
away from the box, you can insert a screwdriver blade and twist the rest of
it away.  This doesn't put a great deal of pressure on the fittings.

Of course, taking care of the knock-outs *before* you mount the device is
always the best solution, but often times I'm not there when they're
installed.  The sprinkler guys I work with all leave one of the knock-out
holes punched out for later connection.  Some even leave plastic plugs in
place.  Now *thats* thoughtful.