View Full Version : Sprinkler Blow out question:
Martinjmpr
09-30-2018, 10:50
Last year I hired someone to blow out the sprinklers but I took pictures and had him show me what to do so I could do it myself this year.
Just tried, did everything he showed me but got nothing coming out of the sprinklers when I had the compressor hooked up.
I'm thinking that maybe it's because I have a very small "Pancake" type compressor, does that sound right? So what is the minimum size of the compressor/tank that people are using to blow out sprinklers? I don't really want to get another compressor as the pancake compressor seems to work fine for everything else I need it for.
BPTactical
09-30-2018, 11:21
The pancake should do it, you just don't have much air volume to work with so it will take a while. Use the manual bleeder valves for each zone valve instead of relying on the manual setting on the clock.
Leave all ball valves @ 45 degrees, don't forget to purge the backflow preventer as well.
Martinjmpr
09-30-2018, 17:17
The pancake should do it, you just don't have much air volume to work with so it will take a while. Use the manual bleeder valves for each zone valve instead of relying on the manual setting on the clock.
Where would those be and what would they look like? Last year the sprinkler guy just hooked up his compressor and manually cycled through the zones in the control panel.
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SideShow Bob
09-30-2018, 19:08
On most residential irrigation systems just turn the solenoid on the valve body to open the manual setting to open. There should be markings on the body referring to open & clsed.
BPTactical
09-30-2018, 20:48
On most residential irrigation systems just turn the solenoid on the valve body to open the manual setting to open. There should be markings on the body referring to open & clsed.
Need to be careful turning solenoids, there is an adjustment range for most solenoids and when you go turning them that goes out the window, sometimes as little as 1/8th turn makes the difference between a correctly functioning valve, a stuck shut or a stuck open.
Residential valves usually have a bleeder screw or knob on the top of the valve, also known as the bonnet. Contact Denver Brass or another large irrigation supplier, be sure to have the brand and model, likely a Rain Bird or Toro - they can give you the bleeding procedure for them.
SideShow Bob
09-30-2018, 21:45
You can search the make & model on the interwebz for the procedure if you’d upgrade the 56 K dialup......... Oh, right, Your commadore 64 couldn’t handle the upgrade. [Tooth]
fairrpe86
09-30-2018, 21:57
Like BP said, contact DBC Irrigation with at least the brand of valve and they can tell you proper bleed procedure. Pretty easy process to do, just takes some patience with a smaller compressor.
Martinjmpr
10-01-2018, 08:22
Thanks for all the advice but at this point my inclination is to either see if I can borrow a bigger compressor or just call the guy I had come out last year. He did mine for $35.
beast556
10-01-2018, 09:49
Your compressors if probly fine. I used a 3gal for years to blow my system out. 2 years back I upgraded to a 6gal and it works even better now. Sounds like you have one of the ball valves closed off not letting the air in to the system.
The little bleeder screw should look something like the ones below . . . the little black "thingy" next to the big black thingy (the solenoid). You just unscrew those a little bit one zone at a time to open the valve and to blow out that zone. Then close it and do the next one. Seems like it would take forever with a pancake compressor. I used to try to use my 15 gal and that took a looooong time. I found a 33 gal on CL several years ago and that's worked pretty well--has a bit more CFM and a bigger tank.
The process isn't very hard once you do it once. I was kind of intimidated to try it for fear of screwing something up . . . but watched a bunch of videos and it's not hard at all. Just a little time consuming. $35 is a pretty good price it seems these days, so maybe the convenience is worth something.
https://images.truevalue.com/OR/Item/1738/large
Sometimes, instead of a screw where the little black thingy is, it's a switch that you can flip open or closed.
Well, I was going to wait another couple weeks to blow out the lines, but it was supposed to get pretty cold last night and supposed to get really cold overnight for the weekend. So I ended up winterizing the system last night. 33 gal Craftsman compressor seems to handle it fine, although still takes about an hour just letting it recover and I'm paranoid about having lines freeze . . . so I usually hit each zone twice. It's probably overkill but an extra 30 mins vs a lot of digging and heartache later seems worth it.
Sometimes I think about trying to pick up a better gas-powered compressor with higher CFM, but not sure it would be worth it in the long run financially vs the potential time savings each year over what I use now.
I use a 26 gallon Craftsman compressor and blow out each line twice.
the first time forces out the large amount of water, the second time gets a lot of vapor that would freeze sitting in the sprinkler heads over the winter.
I have six zones, each takes about 10 minutes, hour total. Must be careful how much pressure ( under 50 pounds) goes in the line the first pass or I rupture a two bit gasket in the anti siphon valve.
ChickNorris
10-09-2018, 11:09
Ok I'll bite. Since you didnt specify your current HP or CFM & only the 1 use, here's my 2 cents: Unless you're planning to run multiple pneumatic tools @ the same time or run a torch for 30 mins or more at short rest intervals while in the field, or you want to moonlight & winterize systems & eventually turn a profit, I don't see much advantage over what you've got now, it gets the job done. : )
The weather forcast got me worried so I blew out the system last night.
I have a bigger Kobalt compressor. Puts out 5.9cfm at 40psi and is louder than hell. Ideally you need 8cfm+ but like CN said you can do with less. If you got a good neighbour ask to borrow their compresor and simease the outputs.
beast556
10-09-2018, 19:04
Just blew out my system with the 6 gal mentioned earlier. Works great took 25 minutes total.
Ok I'll bite. Since you didnt specify your current HP or CFM & only the 1 use, here's my 2 cents: Unless you're planning to run multiple pneumatic tools @ the same time or run a torch for 30 mins or more at short rest intervals while in the field, or you want to moonlight & winterize systems & eventually turn a profit, I don't see much advantage over what you've got now, it gets the job done. : )
Yeah . . . I am pretty sure the numbers wouldn't add up to upgrade barring some unusual find. Mine's a 6HP 33-gal Craftsman (8.6 scfm @ 40 psi / 6.4 scfm @90 psi) that I scored on CL several years back. It gets the job done, just takes some time. I have no interest in doing winterizing for anyone other than myself. I literally use that compressor once a year for the sprinklers. I have a 15 gal Craftsman (also a CL buy that I bought first) and a little Harbor Freight pancake compressor that I use all the time since it's so portable.
ChickNorris
10-09-2018, 19:59
Yeah . . . I am pretty sure the numbers wouldn't add up to upgrade barring some unusual find. Mine's a 6HP 33-gal Craftsman (8.6 scfm @ 40 psi / 6.4 scfm @90 psi) that I scored on CL several years back. It gets the job done, just takes some time. I have no interest in doing winterizing for anyone other than myself. I literally use that compressor once a year for the sprinklers. I have a 15 gal Craftsman (also a CL buy that I bought first) and a little Harbor Freight pancake compressor that I use all the time since it's so portable.
I hear you about upgrades. If I happened across a nitro methane powered compressor for a song, well... I might just have to have that. Wonder how many feet of hose I'd need to hook up the surrounding blocks to make it worth firing up & the subsequent rebuild.
[mlp]
1.5 inches of snow this morning, 32 degrees. There is enough ground heat that i am not worried about the system freezing for a day or two. Then i will blow out the system.
The weather forcast got me worried so I blew out the system last night.
I have a bigger Kobalt compressor. Puts out 5.9cfm at 40psi and is louder than hell. Ideally you need 8cfm+ but like CN said you can do with less. If you got a good neighbour ask to borrow their compresor and simease the outputs.
I actually tried this once with my 33 gal and my 15 gal and it didn't seem to be working well (not "better" than just using the 33 gal by itself). But it's highly possible that I didn't know what I was doing. LOL. I had looked at some videos and tried running lines from both outputs into a T and then a single hose from that to the sprinkler blowout connector. Maybe next year I'll try it again and see if I can figure it out.
ChickNorris
10-11-2018, 07:58
Aw come on, not even a giggle about my 'upgrade'?!
BPTactical
10-11-2018, 08:17
Aw come on, not even a giggle about my 'upgrade'?!
Bush League trolling.
Surely you can do better.....
ChickNorris
10-11-2018, 08:51
Bush League trolling.
Surely you can do better.....
Yay! Acknowledgement.
Yeah yeah I know kinda random. But I admit it made me giggle to think of how many people might read that & roll right past without getting 'it'.
Funny or not.
Sunny and in the fourties. I am going to blow out my sprinkler system. Grabbing essential tools now. Ear muffs, pliers, beer and potato chips.
Sunny and in the fourties. I am going to blow out my sprinkler system. Grabbing essential tools now. Ear muffs, pliers, beer and potato chips.
Hmm. I get the pliers, beer and chips. But what are the ear muffs for?
Blew mine out this afternoon. I usually wait until some time around thanksgiving but but seemed prudent to do it a little early this year.
BladesNBarrels
10-14-2018, 10:23
With temps predicted to a low of 12-15 degrees depending on which station you watch in the Metro Area, it would be prudent to blow out the sprinkler system.
The alternative gets expensive in the spring.
Just sayin'
Martinjmpr
10-14-2018, 16:39
With temps predicted to a low of 12-15 degrees depending on which station you watch in the Metro Area, it would be prudent to blow out the sprinkler system.
The alternative gets expensive in the spring.
Just sayin'
Little late now... temps haven?t been above freezing all day.
Sent from my iPhone using Tapatalk
ChickNorris
10-14-2018, 16:59
Hmmm... ...what are the ear muffs for?
Mickey Mouse impersonations
The compressor is very noisy, especially in the garage echoing off the walls. So, I grab my shooting ear muffs to mitigate the sound.
Still the most vital equipment is the beer.
SideShow Bob
10-18-2018, 18:21
Well,
The neighbor to the south of me didn?t drain or shut the water off to his irrigation back flow. It finally thawed out today, and was spraying water all day until he got home about a half hour ago.
If it were not behind a locked fence, I would have hobbled over and shut it off externally for him.
Yea I wrapped mine with insulation till I had time to blow them out on Monday.
My60 gal blew them out like a champ.
Anyone blown out their systems already . . . or planning on doing it before the cold hits briefly next week? Talking about lows around 20 Wed into Thurs. But then looks like it will warm back up again?
Haven't decided yet if I'll just blow mine out beforehand and call it a year. Tempted to just drain out the exposed pipes and blow out the one drip line I have that would be most exposed but use the system for a couple more weeks after the cold passes. But the "play it safe" in me says to just blow it all out and break out the manual lawn sprinkler a few times.
Thanks. I knew it was going to cool down a bit but had no idea it was going to get that far below freezing.
Probably blow mine out tomorrow after work and call it a season.
Thanks for all the advice but at this point my inclination is to either see if I can borrow a bigger compressor or just call the guy I had come out last year. He did mine for $35.
For $35 why would you even bother to do it yourself.. you?ve already wasted how much time doing it and then posting here when what you did din?t work.
Rachio is great for blowouts.
I can setup a short cycle and soak schedule to give the compressor time to recover and run it a few times until clear while I'm out winterising other stuff. Open the drain valve, pull off the vacuum breaker. Done. I did all my stuff yesterday. Sprinklers, RV, boat, power washer.
I hate blowing them out early as I usually forget to water the south facing lawn and it gets trashed. Once it starts raing more they get turned off. Will go wrap the above ground stuff next and is should be ok for the 3 cold days. If the below freezing continues next week then I will dry er up.
Thanks for the tip on the Rachio. I use to do short manual runs per zone on my old timer.
asystejs
10-06-2019, 17:50
I winterized both my sprinkler systems and the evaporative cooler today
Gotta go help a family member do theirs tomorrow.
SideShow Bob
10-06-2019, 21:56
Got mine scheduled for the 17th. If it gets really cold before then, i will shut the feed off & drain the manifold and back flow preventer.
Since it's supposed to warm up again and I'm trying to get my poor front lawn to recover, I'll probably just drain down to the manifold and the inside valve. Then I can just turn on the inside valve after it warms up and I'm good to go again.
Since it's supposed to warm up again and I'm trying to get my poor front lawn to recover, I'll probably just drain down to the manifold and the inside valve. Then I can just turn on the inside valve after it warms up and I'm good to go again.
I'm kind of thinking I'll do that same kind of thing. I have one drip line above ground and one zone in front with a section above ground that are susceptible to freezing. Will probably drain out the breaker/pipes & manifold and blow out those 2 zones real quick. Then will start it back up after the cold snap and run the system another couple weeks while it's warm. It's kind of a pain, but probably less than manually watering several times.
Might all be fine covering up the outdoor lines and riding it out . . . but the drawbacks if it freezes far outweigh the work to play it safe.
Fortunately I have enough grade that the sprinklers naturally drain pretty well when I open the valves. I've gone winters without blowing out with no ill effects.
Martinjmpr
10-07-2019, 13:12
OK, I'm trying this again. I figured out what I did wrong last year (it had to do with the little screw on the side of the air inlet) and plugged my little Porter-Cable compressor in last night.
It seemed to work OK on the closer sprinklers but on the ones farther away, it didn't seem to have enough 'power' to blow them out.
So here's my question: What specific "number" do I need to be looking at to give me enough power to blow the sprinkler lines?
My current compressor is as follows:
Porter Cable C2002 Compressor
PSI: 150 max
Tank: 6 gallons
2.6 SCFM @ 90 PSI
So what "number" do I need to be bigger? Would a bigger tank help? A bigger SCFM rate?
I don't mind shopping around for a new compressor, but whatever I get, I want it to be big enough to blow my sprinkler lines once and for all (without damaging them, obviously.) I had my compressor running for ~ 2 hours yesterday (I'm sure my next door neighbor hated me!) just trying to get it to get up to 150 PSI before I turned the pressure on to the sprinklers, but it would give me one "blast" of pressure and then not much more after that.
Martinjmpr
10-07-2019, 13:22
OK, so what I'm reading on the Intertoobz says that the required minimum SCFM is 20. Nothing I would be interested in buying is even close.
So it looks like I'll call my sprinkler guy again. He will blow them for $35, and I can't even rent a 20 CFM compressor for less than probably $60 or $100.
I read 8cfm at 40psi is good enough and I think that is right. I had 2 compressors siamesed once and it was about 9cfm, which did the job quickly.
By default I run my Kobalt oilless which I think does about 6cfm at 40psi. This rewuires two cycles but no issues for the past dozen years.
OK, so what I'm reading on the Intertoobz says that the required minimum SCFM is 20. Nothing I would be interested in buying is even close.
So it looks like I'll call my sprinkler guy again. He will blow them for $35, and I can't even rent a 20 CFM compressor for less than probably $60 or $100.
Required minimum of 20? Nah . . . you can do it with less CFM than that, it just takes longer and sometimes multiple passes at each zone (if you are paranoid like me). I have a 33 Gal Craftsman that I got on CL years ago and it's rated at 8.6 cfm @ 40 psi. Takes a little time but it works fine.
I've heard people say they use even smaller compressors than that. But I tried it with a 15 gal I have and it just didn't have the oomph for my setup. That's why I had my eye out for something like the above.
The issue for me is tank volume. You can dump a lot of air through the lines pretty quickly. If the pressure drops too low the backflow preventer will lose its seal. Once that happens, I have no way to get it to reseal using just air.
mahabali
10-07-2019, 17:16
I’m thinking I may just unhook hoses and cover exposed pipes. I blew out sprinklers early Oct 2 years ago and then it got nice for a month and my yard turned brown.
The issue for me is tank volume. You can dump a lot of air through the lines pretty quickly. If the pressure drops too low the backflow preventer will lose its seal. Once that happens, I have no way to get it to reseal using just air.
There should be a cutoff valve between your valves and your back flow preventer. Your air hook up should be after the valve to the bf.
Project time!
beast556
10-07-2019, 18:58
I use a ridgid 6gal compressor for my yard and have no issues. Are you letting it pressure it up all the way?
I had the same issue with not enough pressure to keep the backflow "plunger" sealed using the connector closer to the house . . . but I had 2 quick attach connectors on ball valves on there already and I just flipped one 180 degrees so the shutoff was still between the breaker and the manifold but the hose connector was on the other side of the shutoff. I just shut that off to blow out the system and it eliminates needing to have the pressure to hold the plunger in the sealed position. All the air just goes right down the line to the sprinklers.
Just blew my system out about an hour ago. Hit each zone once to just clear things out ahead of the cold. Planning on turning the water back on again probably Sunday, since the warm weather looks like it will make a return for at least a couple weeks. Want to be able to water just a bit longer, so I'll have to do a more thorough blowout in a few weeks.
There should be a cutoff valve between your valves and your back flow preventer. Your air hook up should be after the valve to the bf.
Project time!
The air connection is after the BF, but there is no valve between the air connections and the BF and no room to insert one. It's easier for me to be careful than to re-engineer the plumbing.
Blew mine out after work today. Just in case.
Need to do tomorrow. I'm sure I'll forget. I've forgotten the sump pump the last two years.
I have a pipe under my deck for a garden hose that I shut off and drain every year. As a reminder, I stuck a note on the sprinkler controls to remind me.
I have a pipe under my deck for a garden hose that I shut off and drain every year. As a reminder, I stuck a note on the sprinkler controls to remind me.
You have to touch your sprinkler controls? That's barbaric. [Coffee]
I love the Rachio 3 controller that I installed this summer. There's an app for that.
BladesNBarrels
10-09-2019, 10:27
You have to touch your sprinkler controls? That's barbaric. [Coffee]
I love the Rachio 3 controller that I installed this summer. There's an app for that.
Is there an app for draining and blowing out the system?
[Coffee]
You have to touch your sprinkler controls? That's barbaric. [Coffee]
I love the Rachio 3 controller that I installed this summer. There's an app for that.
Ha. No. But the water shutoff valve is maybe a foot away from where the control box is mounted so seemed like a good place to post my reminder.
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