SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

David, I dont know how much you were getting charged but in most cases homeowners like yourself will spend to rent a compressor close to the same as what it will cost to have a professional contractor do the blow out. Plus atlkeast in our case we guarantee the system against any freeze damage. As an example to replace a backflow that has been damaged from freeze it can cost you up to $250.00 right off the bat in the spring. If you already own a compressor then its a different story.

David,

Is that $26 compressor what is needed to properly blow out the lines?

My only knowledge of the subject comes from reading Jess's pages at www.irrigationtutorial.com, and he makes it sound like a high-end compressor is needed.

David,

I'm a DIY homeowner who installed my own system (60'x130' lot) this past spring. 8 zones, 15 rotors, 18 sprays and a drip for the wife's planters. I've got a Watts 1" PVB w/ drain-tee (w/ plugged 3/4" female adapter like yours) below it to drain and blow out.

This past week I was able to winterize my system successfully. I'd called around to various local irrigation companies... most were charging $10-15/zone to winterize and turn-up in the spring (w/ guarantee). I hadn't fully decided whether to do it myself or hire it out. The thought of $120 and time off work to let a contractor do it didn't thrill me at all.

I'd read all of the internet resources re: DIY irrigation (obviously) and knew I needed a BIG compressor. Called around and was able to find an Emglo 20CFM 6.5HP compressor for $50/day. Went to Lowes... found a brass adapter to take the 3/4" drain to 3/8" for the AC hose fitting. Picked up the AC from Sunbelt Rentals, back to the house... an hour later I had a winterized system. It was fairly simple, but not something I would have tackled w/o feeling properly informed and capable.

Spend a few evenings reading up and know what you're doing before diving in. Get a large gas-powered compressor capable of delivering at least 15CFM at 40-50PSI (hope you've got a truck and a friend w/ a good back). Crank the pressure down to 40PSI; test it well before you realize the regulator guage is sticky and you launch your rotors. Basically: connect the AC hose into your drain, activate your farthest zone via timer, fire the compressor, connect AC hose to compressor, cycle thru zones @ 1 min. each until you get nothing but a fine mist.

The first time is always a bit unnerving, like anything, but I'll never pay someone to do it as long as I'm able. If you've got the time and are handy in nature, go for it. If you're pressed for time, the temps are dropping and you're not 100% sure of yourself... hire it out this year and plan to DIY next year.

HTH and good luck!

Aaron

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by DavidQ</i>
<br />Renting a compressor starts around $26/half day. The quote I got for having the lines blown was $95. Any input on my questions.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

I just bought a Craftman 3HP 15 Gal compressor and blew out
my 3 head/zone/5 zone system with eaze. I tried connecting to
each of the test cocks, but it seemed to blow out thru the
breaker valve. I ended up using a spiggot adapter I pieced
together from 1/4" QD to 3/4" spiggot swist.

you do not need industrial grade compressors to do the job.
This is the second year I've done it myself in about 1 hour.
The compress cost me $168, and service would have cost me $60
per year. So I'll make back the cost of the compressor in
two years, plus I can use it on so much more.

--
Dan

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by DavidQ</i>
<br />Renting a compressor starts around $26/half day. The quote I got for having the lines blown was $95. Any input on my questions.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

I just bought a Craftman 3HP 15 Gal compressor and blew out
my 3 head/zone/5 zone system with eaze. I tried connecting to
each of the test cocks, but it seemed to blow out thru the
breaker valve. I ended up using a spiggot adapter I pieced
together from 1/4" QD to 3/4" spiggot swist.

you do not need industrial grade compressors to do the job.
This is the second year I've done it myself in about 1 hour.
The compress cost me $168, and service would have cost me $60
per year. So I'll make back the cost of the compressor in
two years, plus I can use it on so much more.

--
Dan

David, did you get an answer to your original question? I have the same valve. I also need to understand how to stop the air from coming through the backflow plunger.

David,
Use the lower of the two drain valves. Keep the top one closed while you are blowing out the lines. You can buy a fitting that will be quick disconnect on one end for the compressor hookup and i think it's 3/8 male on the other. Home Depot has them or any local plumbing shop that carry's sprinkler accessories. I used a borrowed 5.5hp 25 gal craftsman that only gets to about 8cfm at 40 psi. It did the job but slowly. Rentals were $75 per day for the same size compressor and $5 for the fitting. The air would not seat the back flow valve so I needed to use the water pressure to compress the spring then switch to air to blow out the lines. Good luck.