sprinklers...

[Road Guy]

So dumb question, I've been acting like my kids do and watching a lot of YouTube vids on winter sprinkler blowout, it looks pretty simple..

I've got a two stage "hot dog" compressor and it looks like I just hook it up to the valve thing on the outside of my house and then set each zone to run for maybe 30 seconds?

Ive been paying a guy around $50 bucks each winter to blow them out but this year he wants $75 - o hommie aint playing that shit

Seems more simple than I thought, should have looked at before but am I missing something?

 

[Dleg]

Isn't most lawn irrigation piping made out of HDPE?  If so, that stuff can handle being frozen full of water.  Trust me on that...  but yeah, probably a better idea to blow it out. 

 

[FLBuff PE]

I'm not sure the typical homeowner compressor pushes enough CFM to blow out the system. My guy (across the street neighbor) rents a tow behind diesel compressor.

 

[Dleg]

I'd be super careful doing anything with an air compressor and irrigation piping, especially a commercial high-CFM model..  If for some reason the piping gets blocked, you can very quickly exceed the pressure rating of the pipe and blow a fitting or burst the pipe.  You don't need to get all the water out of a pipe system to prevent freeze breakage - you really only need to create some space for the ice to expand into as it forms. So leaving some water in pipe bellies should be OK. 

 

[Road Guy]

Seems like the intel is to set the compressor to 50 psi and then turn each zone on seperately- I'm gonna give it a whi this weekend and see if I can see air coming through all the different heads in each zone.

 

[Dexman PE PMP]

It really isn't that hard. I used my compressor to blow out the sprinkler system every year. 

Basically:

• Shut off the main water supply to the sprinkler system inside the house
  
• close the butterfly valves on the backflow preventer
  
• open the drain in the valve box, once the water spills out, attach the compressor (you'll need an adaptor and it depends entirely on what type of hose connection you have and the size of the drain connection point. I made my own with fittings from Home Depot for $10)
  
• one at a time, manually activate each zone and let it run until all sprinklers in that zone are blowing air, then close that valve
  
• disconnect compressor
  
• open the butterfly valves on the backflow preventor to halfway
  
• open the remaining drains to clear any "low" spots (including any near the main water supply valve)
  

The important thing to keep in mind when using your own air compressor is that you do not exceed 40 psi. Most home compressors cannot maintain that type of pressure and still provide adequate flow rate to activate all of the sprinklers. Even my larger tank compressor would need to recharge between zones. That sucked because it would take 4-5 minutes to recharge and I had 9 zones, which meant I spent almost an hour doing it with only about 5 minutes of actual work.

 

[Road Guy]

I've got a similar set up to this:



Do I need to go into each Valve box or use the hookup like above?

 

[Dexman PE PMP]

You can hook up there, no problem.  Just make sure the valve between the hose and the siphon break is closed. I've heard debate as to whether the compressor can damage it, and it's easy insurance. Basically, you're tricking the system to run on air instead of water.

 

[Road Guy]

What I found online is very similar to your write up. 

I just hate dealing with these types that "blow" through your neighborhood this time of year and then also try and upsell aerations, fertilization, etc.. figured since I have the compressor no sense dealing with the local meth community if I don't have to..

thanks for the intel.......

 

[Dexman PE PMP]

We used to use Scotts Lawn Service for fertilizer treatments. Something like $30 a month and they handled all of the required chemicals for the lawn throughout the year. It was a bit more expensive than doing it myself, but it was one less thing I had to worry about.  Every year, about this time I would get a couple phone calls and an email from them asking if I would be interested in them doing a full "winterization" package that included aeration, overseeding, and blowing out the sprinklers. Because I was a valued customer, I was given the "low" price of $350. If I only wanted the sprinklers, that was somewhere around $100.  The first year I just paid one of those neighborhood hopping guys $20 (those ones who have a truck and a compressor/trailer and go door to door), but learned how to do it for the other few years.

The hard part is getting a good compressor capable of doing it. You need one that can do both the pressure but also maintain a flow rate for 20-30 seconds, and those ones aren't cheap. I just happened to have one because I had a bunch of air tools to work on the car.

 

[Audi Driver P.E.]

The main reason I don't do mine, myself is because of the volume of air required to accomplish the task.  I have 9 zones and almost an acre of yard.  The typical homeowner compressor tank doesn't have the required volume.  I did it once with a borrowed compressor and it took forever.  Those guys with the trucks come by and are done in about 5 min per zone.  They spend a little more than an hour at my place whereas it took me most of a day.

 

[Road Guy]

I live in “new” Colorado, which has the terrible California housing concept, so I’ve got like a .22 acre lot, I think I have 4 zones. I’m going to give one a whirl this weekend. I cant see it taking more than an hour.

Like most things my main motivation for doing things myself is not having to take off work and wait for someone to come to the house to do something.

I am actually thinking of getting a larger compressor for the wood floor I am going to install in my house, they really have come down in the last 10 years, but the one I have is a Bostitch and will run floor framing nail guns all day long..

 

[Audi Driver P.E.]

I installed wood flooring in my last house using a pancake compressor and floor nailer (BTW, get the floor nailer they sell at Lumber Liquidators).

 

[mudpuppy]

Isn't most lawn irrigation piping made out of HDPE?  If so, that stuff can handle being frozen full of water.  Trust me on that...  but yeah, probably a better idea to blow it out. 

Perhaps the piping can handle it, but the valves, tees, and heads cannot.  I learned this the hard way and had to replace a good portion of my sprinkler system at my old house.

I did a lot of research on this afterwards and pretty much found that your typical homeowner compressors can't maintain enough flow at a low enough pressure to blow out the lines.  You don't want the pressure too high or the flow too low.  This was nearly 15 years ago, but I vaguely recall they were recommending about 20 CFM, and most compressors run at most about half that.  I just gave up and hired someone to do it for $75 and then never used the sprinklers again.