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DieselDeere
10-04-2004, 11:37 PM
I have a two questions about commercial blow-outs. First how do you properly winterize a 21 GPM 1.5" system with a 1/4" test valve on each of the 1.5" ball valves? Second how much would you charge for a 16 zone system of this size with a 185 air compressor. Thanks in advance.

activelandscaping
10-08-2004, 08:29 PM
1) RPZ or PVB ?
2) how do you know this is 21 gpm ?
3) 1.5" we charge 12 bucks/zone ( min 6 zones ).
4) what size are the valves ?
5) you need to sweat in a boiler drain after the backflow device, if there isn't one allready.

Jim

Critical Care
10-10-2004, 12:50 AM
I suppose that when blowing out the system the 21 gpm figure doesn't really enter in the equation. It kind of sounds like what I'm up against. Can you push enough air volume through a quater inch testcock to effectively blow out that 1.5" line? Doesn't sound promising.

Yep, it would be great to install that drain, or stub out. For me, I can't take the time to do this for all the systems that don't come equipped with this. That can be a money making project for next season. If you have the time, charge them $40 - or whatever - to install the drain or stub.

greenworldh20
10-10-2004, 02:29 PM
for commerical accounts we charge $90 to winterize up to 6 zones. over that is $10/zone.


that building will take 1 hour...including in this one hour is drive time, finding shut off valve, setting up compressor, winterizing system by timer, disconnecting compressor hose...

brian

DieselDeere
10-20-2004, 09:13 PM
It is a PVB
21 GPM was marked on the controller
1.5" valves
Also if did install a boiler drain after the PVB and hooked up the compressor at the boiler drain would there be any diffrence compaired to winterzing a Febco 765-1?

activelandscaping
10-20-2004, 10:10 PM
At this pointe I would skip the boiler drain and install a 1/2" bronze saddle tee ( for 1 1/2 pipe ) on the discharge side of the vacuum breaker.

You can just give the size of the VB, the make, model number doesn't really matter. In res. and commercial you will have 1" VB, 1 1/2" VB and 2" VB ( if you see a 3/4" VB you know it's a sh** job or a HO install ). But they all work, and winterize by the same process.

Reduced Pressure Zone back flow preventer's ( RPZ's ) are usually installed for reasons concerning grade and/or contaminate risk. RPZ's require special care, with a RPZ the type is important.

If the 21 is on the controller, as part of the Mfg., it probably means you have a controller capable of 21 zones.

If you post the make and model controller I will give you the procedure for winterizing.

Regards,
Active

Mdirrigation
10-20-2004, 10:15 PM
You wont get the volume of air necessary to blow out that system thru a 1/4 inch test ****. Its like blowing thru a straw, explain to the owner that a blow out point needs to be installed to properly do the job . Odds are that if you dont and try to do it thru a 1/4 inch firring there will be freeze damage that you could be held responsible for.

DieselDeere
10-22-2004, 04:11 PM
If you post the make and model controller I will give you the procedure for winterizing.

Regards,
Active

It is a Rain Bird ESP16LX Plus

activelandscaping
10-22-2004, 10:13 PM
One more thing, sorry I forgot to ask. ;)

Is there a way to drain the water between the VB and the shutoff valve? A bleeder elbow or bleeder cap?

Regards,
Active

activelandscaping
10-24-2004, 11:56 AM
Turn off the water inside the bldg.

Hook up your compressor to the saddle tee you installed.

Go to the timer and set the dial to " Auto " then press the program button until (A) is displayed

check to see that there is adequate time on each station ( 10 min ) or better

turn the dial back to auto and press man/advance button ( timer should display station and time remaining )

Start your compressor ( with the valves closed ), then slowly open the valve to about 30 degrees.

Check to see that zone 1 has come up ( remember to step down any 12" pop-ups)

Wait until the last head is no longer spraying a solid stream of water ( blowing smoke ), then go in and hit the man/advance button to go to station 2 ( repeat this until all the zones have been blown out )

After the last station is cleared, but before you turn off the timer, shut down the compressor.

Unhook the compressor line, open both test ports and turn the ball valves on the VB to 45 degrees.

Drain the water between the VB and the inside shutoff and turn the timer to " off "

End of story.

Best of luck,
Active

DieselDeere
10-24-2004, 09:10 PM
One more thing, sorry I forgot to ask. ;)

Is there a way to drain the water between the VB and the shutoff valve? A bleeder elbow or bleeder cap?

Regards,
Active

No there is not.

activelandscaping
10-24-2004, 09:40 PM
No there is not.

Then you will need to place an additional Bronze saddle tee in the bottom of the pipe, on the feed side of the vacuum breaker. The pipe between the shutoff valve and the VB will remain full of water and could split from freeze damage, unless the VB is inside the Bldg.

BTW, I forgot to mention that a 1/2" MPT boiler drain can be fitted to the bronze saddle tee.


Best of luck,
Active