Sprinkler Blowout with Air Compressor FEBCO 765 Full Guide, FEBCO 765-1 Backflow Preventer PVB shown

This video show the steps I use to winterize and blow out a residential sprinkler system using the test ports on a FEBCO 765 Pressure Vacuum Breaker, or PVB (a type of Backflow Preventer). As covered in the video, using the test ports is not ideal, but it can be done. This video also shows the internal parts of the FEBCO 765 PVB, including how to disassemble or repair the PVB. The video also includes information about the parts and air compressor used, and some tips that might help you complete this DIY and select parts and equipment. Check below or the Pinned Comment for Timestamps, part numbers, and links.
Timestamps, part info, links:
00:11 Which port? "Ideally neither, but if you must either."
01:26 Difference between the two test ports
02:20 Example of a proper blowout port fitted downstream of the PVB
02:23 Know the rules in your jurisdiction
03:50 Begin - Steps to drain the PVB
04:00 Shut off the water supply to the PVB
04:47 Run the furthest sprinkler zone for a few seconds to depressurize the
system
05:23 PVB is now depressurized
06:08 Drain the water supply pipe
06:36 Close the inlet valve to the PVB
06:48 Open the test port valves using a flat-head screwdriver
How to remove the valves from the PVB
(not necessary to do, but shown in
case you need to make repairs)
07:53 Remove the canopy with a wrench
08:14 Remove the bonnet - turn counterclockwise by hand
09:20 Remove the poppet by hand
09:25 How the air inlet valve assembly works
11:19 Remove the check valve assembly by hand
12:01 See the different paths of the two test ports
13:20 Different bonnets you can buy to perform the blowout
13:54 Inspect and re-install the check valve assembly
15:38 Inspect and re-install the air inlet valve assembly
17:08 Overview and precautions about the Blowout Procedure, using the K-
Rain document (link below)
21:14 A quick look at the compressor shown in the video
21:32 Use the shortest hose of the largest ID
21:58 Don't use an extension cord
22:24 Compressor pressure setting - 50 psi,
optimize flowrate
Begin the blowout:
24:04 Hook up the hose to one of the test ports
24:41 Open the furthest zone valve before introducing air to the sprinkler
system
25:21 Introduce air to the system
26:03 How to manually trip the inlet valve to close
26:16 Check the sprinklers to see that they'd popped up and are spraying
water out - run for only 1 minute
26:44 After one minute, shut off the air and disconnect the hose
26:54 Close the zone valve
28:16 Same process, shown for another zone
28:37 Same process again, for another zone - multiple passes will likely be
required with a smaller compressor
29:49 Same process again, this time on the lower test port
30:43 Turn off the sprinkler controller and unplug it
32:22 Exercise the valves, then turn all valves to the "45 degree" position
34:40 How to turn the sprinklers back on (spring-time start up)
37:01 Info about the hose and fittings shown in this video:
short 3/8" ID air hose: Harbor Freight item # 91294
shut off valve: Harbor Freight item # 63553
high-flow fitting: Harbor Freight item # 63546
38:38 Another option if you can't find a flare fitting to fit the test port
40:01 Information on the air compressor shown in the video and general air
compressor information
K Rain Winterization document, PDF:
www.krain.com/...
www.krain.com/...
Colorado State University Winterization document, PDF:
extension.colo...
I hope this video was helpful for you. Thanks for watching, and good luck with your winterization! : )

[@L35inColorado]

Timestamps, part info, links: 00:11 Which port? "Ideally neither, but if you must either." 01:26 Difference between the two test ports 02:20 Example of a proper blowout port fitted downstream of the PVB 02:23 Know the rules in your jurisdiction 03:50 Begin - Steps to drain the PVB 04:00 Shut off the water supply to the PVB 04:47 Run the furthest sprinkler zone for a few seconds to depressurize the system 05:23 PVB is now depressurized 06:08 Drain the water supply pipe 06:36 Close the inlet valve to the PVB 06:48 Open the test port valves using a flat-head screwdriver How to remove the valves from the PVB (not necessary to do, but shown in case you need to make repairs) 07:53 Remove the canopy with a wrench 08:14 Remove the bonnet - turn counterclockwise by hand 09:20 Remove the poppet by hand 09:25 How the air inlet valve assembly works 11:19 Remove the check valve assembly by hand 12:01 See the different paths of the two test ports 13:20 Different bonnets you can buy to perform the blowout 13:54 Inspect and re-install the check valve assembly 15:38 Inspect and re-install the air inlet valve assembly 17:08 Overview and precautions about the Blowout Procedure, using the K- Rain document (link below) 21:14 A quick look at the compressor shown in the video 21:32 Use the shortest hose of the largest ID 21:58 Don't use an extension cord 22:24 Compressor pressure setting - 50 psi, optimize flowrate Begin the blowout: 24:04 Hook up the hose to one of the test ports 24:41 Open the furthest zone valve before introducing air to the sprinkler system 25:21 Introduce air to the system 26:03 How to manually trip the inlet valve to close 26:16 Check the sprinklers to see that they'd popped up and are spraying water out - run for only 1 minute 26:44 After one minute, shut off the air and disconnect the hose 26:54 Close the zone valve 28:16 Same process, shown for another zone 28:37 Same process again, for another zone - multiple passes will likely be required with a smaller compressor 29:49 Same process again, this time on the lower test port 30:43 Turn off the sprinkler controller and unplug it 32:22 Exercise the valves, then turn all valves to the "45 degree" position 34:40 How to turn the sprinklers back on (spring-time start up) 37:01 Info about the hose and fittings shown in this video: - short 3/8" ID air hose: Harbor Freight item # 91294 - shut off valve: Harbor Freight item # 63553 - high-flow fitting: Harbor Freight item # 63546 38:38 Another option if you can't find a flare fitting to fit the test port 40:01 Information on the air compressor shown in the video and general air compressor information K Rain Winterization document, PDF: www.krain.com/winterize-your-sprinkler-system www.krain.com/content/files/images/landingpages/winterization/winterizeyoursprinklersystem.pdf Colorado State University Winterization document, PDF: extension.colostate.edu/docs/pubs/crops/04719.pdf I hope this video was helpful for you. Thanks for watching, and good luck with your winterization! : )

[@carlosaracil7980]

You should get a KZbin award for the level of detail in your video!

[@L35inColorado]

Haha, thank you, and thanks for watching! : )

[@jasperficara5095]

I am 80 years old; I've watched many KZbin videos over the years, but your video was amazingly good--ironically, I almost didn't watch it because of it's length--really glad I did. The level of detail, the diagrams, the degree of completeness right down to excellent camera work (proper lighting, steady image, correct subject selection, clear sound level, etc.) were generally well beyond what I've seen most other DYI producers generate--even for some of the pro productions. I especially liked the discussion regarding the PVB (I installed a Wilkins 720-A few years ago). The clear diagram you included really helped. The down to earth explanation and brief discourse on the relationship of pressure vs. volume and CFM(volume) and CFM(mass) were quite helpful--especially your explanation exposing the misleading horsepower and volume ratings on your compressor. It answered a question I've always wondered about. I wish I had viewed your video before I bought a Harbor Freight McGraw 20 gal, 135 psi, 4.0 CFM (oiled) compressor @$200. Great work; you've got a lot to say. Best wishes on your future production.

[@L35inColorado]

Wow, thank you very much for your kind comment! I'm so glad that the video helped: thank you for watching, and thank you for such a nice comment : )

[@jimcompton8638]

This video was worth its weight in gold! So much detail. Thanks so much!

[@L35inColorado]

Wow, thank you so much for your Super Sticker, and thanks for watching! : )

[@esquare123]

Thanks for the detailed video!

[@L35inColorado]

Wow, thank you so much for the Super Thanks! And thanks for watching : )

[@mrhos86]

Most informative KZbin video I’ve seen in a long time.

[@L35inColorado]

Thank you, and thanks for watching! : )

[@NatureRUsLandscaping]

Wow! What an excellent instructor! I felt like I was in a technical school program classroom. You are very knowledgeable, and your demonstration was very clear and on point.

[@L35inColorado]

Thank you, and thanks for watching! : )

[@NatureRUsLandscaping]

@L35inColorado You are very welcome. I'm looking to add winterization to my landscaping business. This is the best video tutorials I've seen. I'm still learning about the irrigation system.

[@MatthewSwartz-w1h]

Off all the instructional videos, this was the only one that actually helped me - I can't believe no one else demonstrated the manual operation of the PVB valve manipulation. Thank you for publishing this - hopefully saved me a bunch of money!

[@L35inColorado]

Thank you, and thanks for watching! : )

[@Masterofnothing73]

Thanks!

[@L35inColorado]

Wow, thank for so much for the Super Thanks! : )

[@macdonagh313]

Wow, you are the best. Your knowledge is incredible, and so is your voice!

[@L35inColorado]

Thank you, and thanks for watching! : )

[@darin8999]

This is probably the best instructional video ive ever watched.

[@L35inColorado]

Thank you, and thanks for watching! : )

[@tonydooda9449]

This should be the go to video for Sprinkler Winterization excellent job well done

[@L35inColorado]

Thanks! : )

[@jimphipps6711]

Excellent detail in your video. I was able to get the PVB to seal when blowing the upper test cock using your procedure of lifting the poppet with my fingers. Worked great and I was able to use my small 3 gal tank compressor to blowout my sprinkler zones. The only thing I did differently was to leave the air pressure on while switching between zones at the controller. Saved a lot of walking back and forth. I had the pressure regulator set to 50 psi but actual pressure was much lower due to a small capacity compressor. Still worked great and did not subject the system to damaging pressure transients during switchovers. Thanks for making your video. Jim P., Lakewood, CO.

[@L35inColorado]

Outstanding, thank you for watching, and thanks for adding your tips! : )

[@JJSP117]

Wow, great video! You are highly intelligent and so well spoken that I was not lost in your explainations. Some people try and dumb things down to try and make it simple but lose an audience; you provided some high level detail and kept me intrigued. I have same setup and I’m really interested in how you will upgrade to blow out after the back flow preventer and only doing this as a one time! Please upload that video soon and thanks again. 🎉

[@L35inColorado]

Thank you, and thanks for watching! : )

[@glengibson]

Great job on this video! I needed the help with a failed attempt at blowing out my system. I really appreciate your detailed explanations.

[@L35inColorado]

Thanks, and thanks for watching! : )

[@juyoung3671]

This video solved my issue! My air compressor couldn't blow out the water at all. Air looked leaking. 25:50 From your video, I could finally blow out the water. Thank you for your excellent video!

[@bmorg57]

Best video of blowing out Febco backflow preventer, including how the bonnet, poppet and check valves work, as well as how to inspect them! If she has other videos I plan to check them out. ALso glad to see a knowledeable female doing this, since I'k a woman who does most of my own home maintenance and home improvements.

[@L35inColorado]

Nice - thank you, and thanks for watching! : )

[@slab817]

This is the most detailed walk-through video I've come across - very nicely done!

[@L35inColorado]

Thanks, and thanks for watching! : )

[@swren7]

Thank you for this awesome video! You gave a crystal clear explanation & illustration. That's what I need.

[@L35inColorado]

Thanks, and thank you for watching! : )

[@Leo-kc1mg]

Like everyone said, it's a super detailed video. A lot of knowledge and work is packed in this. Even though I have done winterizing on my own a couple of times some steps I simply forgot and it really made me feel dumb. After watching this video I understand better how everything works and I loved the tip of lifting the spring to help the check valve since I'm using a pancake air compressor. Thank you so much L35! I will surely watch for your future videos and save this video for next year in case I forget how to winterize! 😊

[@L35inColorado]

Thank you, and thanks for watching! : )

[@Majeskty]

Excellent with lots of detail you don’t see in other videos!!! Very clear on instructions and presentation! Wish that Winterization manual you had was linked or had a PDF for downloading for reference. Thank you for such a gem of a video for Winterization of the Sprinkler System, plus showing the guts of the Back-Flow Preventer etc., detail, detail, detail, EXCELLENT!

[@L35inColorado]

Thanks - if you mean the K-Rain Winterization document, it is linked in the Pinned Comment (as well as some other documents) and here is the PDF: www.krain.com/content/files/images/landingpages/winterization/winterizeyoursprinklersystem.pdf I hope that helps - check the Pinned Comment for more info. Thanks for watching : )

[@Majeskty]

@@L35inColoradoThanks!

[@johnm.8742]

Such a great video! Thanks for the help. I was trying with small compressor, and your tip to pull up poppet by hand is what I needed.

[@L35inColorado]

Nice - good luck, and thanks for watching! : )

[@Digiur]

OMG Finally some _actual_ good information! Not just the same copy/paste BS! Thank you!

[@silvertortiose]

Amazing video! Appreciate the in depth instructions, and explanation on each step (and why they are important).

[@L35inColorado]

Thank you, and thanks for watching! : )

[@thesunisbright3]

Very good video with the added diagrams and well extremely well explained.

[@L35inColorado]

Thank you, and thanks for watching! : )

[@Danumals]

This is extremely helpful and valuable. Thank you.

[@L35inColorado]

Thank you, and thanks for watching! : )

[@Katy-Did]

Excellent video! I always wondered how this was done. We have to get our back flow certified at start-up in spring, but it is nice to know we can save some money and blow out our own system.

[@L35inColorado]

Yes, it's a great way to save a hundred bucks or so! Thanks for watching : )

[@themapisnottheterritory]

You are awesome at this. Smart, concise, super useful!

[@L35inColorado]

Thank you, and thanks for watching! : )

[@xdragonflame6563]

This is exactly what I was looking for. Thanks

[@L35inColorado]

Thanks, and thanks for watching! : )

[@Mercedesdriver2012]

hello, great video 👍.best regards and a nice weekend from Germany 🙌😁

[@L35inColorado]

Thank you! : )

[@carpediem4413]

Awesome video with great detail… 😊

[@L35inColorado]

Thank you, and thanks for watching! : )

[@bencordes2899]

EXCELLENT video! Thank you !

[@L35inColorado]

Thank you, and thanks for watching! : )

[@MoonerBros]

Absolutely the best explanation and detailed video. Super thanks !!!!🎉🎉🎉

[@L35inColorado]

Thank you, and thanks for watching! : )

[@GreenandGrowingOfCoS]

You're the first person to ever show this to everyone. Thank you

[@L35inColorado]

Thank you, and thanks for watching! : )

[@Reve-zg2mf]

Wow! Great video. Thank you!💯

[@L35inColorado]

Thank you, and thanks for watching! : )

[@johnscott2940]

Thank you. This is a great instructional video . Very well made and you actually cover everything. You explain the steps the why and the how to. Best instructional that I’ve seen in a long time.

[@L35inColorado]

Thank you very much, and thanks for watching! : )

[@tcbkkb1]

Excellent job! Cheers!❤🎉

[@L35inColorado]

Thanks, and thanks for watching! : )

[@iblebible00]

A little out of season for me, but thank you for the video! Trying to learn about BPVs and irrigation system maintenance - I think I've gained more context and understanding here than all of the other videos I've watched combined. I feel one step closer to solving my irrigation nightmare!

[@L35inColorado]

Thank you, and thanks for watching! : )

[@TheSkeptic_1]

I want to start by echoing everyone else's sentiments. This video, your hard work put into it, and the result are just excellent. I learned a LOT. I'm curious about why the 1 min max run time per zone? I have seen many - less thorough - videos on the DIY approach to this, and the only mention of time per zone tends to be where pressure is no longer able to provide adequate CFM and you have to let it build back up in the tank.

[@L35inColorado]

Thanks - the "1 minute limit" is based on the K-Rain Winterization document (linked in the Pinned Comment, and here: www.krain.com/content/files/images/landingpages/winterization/winterizeyoursprinklersystem.pdf ). On page 2, #5, it reads: "Sustained heat from the compressed air may damage pipe and other components. DO NOT blow any circuit more than 1 minute at a time." That "1 minute" K-Rain value was the most conservative value I found when making the video, so I went with that value because a smaller system will get hotter quicker than a larger system, and people watching the video will be working with different sized systems. However, I have also seen "2 minutes" limit, for example in this Rain Bird document (www.rainbird.com/homeowners/blog/blow-out-your-sprinkler-system): "6. DO NOT blow any circuit for more than 2 minutes at a time, as heat from the compressed air can damage the pipes and other components." Both references state that heat is the issue. I hope that helps - thanks for watching : )

[@TheSkeptic_1]

@@L35inColorado Thank you again!

[@tonydooda9449]

Thank you so much for pointing out which of the 2 test port to use for blow out, watched many videos and was not clear as to which port to use --however you answered very clearly either or -again thank you.

[@L35inColorado]

Thank you, and thanks for watching! : )

[@samanthagriffin3207]

THANK YOU! I've watched many videos to determine why the backflow preventer was not seating. Thank you for educating me. Why are irrigation installers not installing a blowout valve on the other side of the backflow preventer? UGH, so frustrating. We'll be getting one installed next year.

[@L35inColorado]

I'm so glad the video helped - thanks for your comment, and thanks for watching! : )

[@Cstoreri]

Thx

[@L35inColorado]

Thanks for watching! : )

[@Synapse7045]

Thanks for this! Great video.

[@L35inColorado]

Thank you, and thanks for watching! : )

[@tomhinde2835]

Great video. I appreciate the time and detail you took in filming and editing. I moved into ahome located in Zone 4a that has a 14 zone sprinkler system and it uses ~ 15 - 18 GPM per zone.. The company I hired to learn on how to properly shut down the system rented a diesel tow-behind compressor to blow the irrigation system out. They spent 30 second to 45 seconds per zone, but there was still quite a bit of moisture coming out. They definitely did not bleed the system until only air was coming out. I had them go back to zone one when they had finished all 14 zones, and I put my hand in front of on of the sprinkler heads, and it got completely soaked. I called the manager, and he said that it was fine, and not to worry. "A little mist is fine" is what he told me. I just replaced 69 heads this year, so I am a little worried. How much water/mist is acceptable? Should I keep cycling through the system with 1-minute intervals until only air comes out? Also, should I be worried that they did not turn any of the valves to 45 degrees to allow for further moisture to bleed out? The manager from the company I hired is coming out tomorrow to inspect. Thanks!

[@carnold.knowledge]

Love your videos. Seems very involved. Is there any way some insulation could be wrapped around everything for the winter?

[@L35inColorado]

It entirely depends on your local climate: here in Colorado, we must drain the PVB and evacuate the sprinkler system ("blow-out") because every year we get severe deep freezes, and anything above the freeze/frost line will freeze and stay frozen (it is not unusual for us to go a week or more during which time the daily high temperatures will not leave the 20's F and overnight lows will be sub-zero F). The freeze/frost line here is also deep (about 3 ft), so obviously the sprinklers are well above that and would freeze if not evacuated. So, here in CO, we must remove the water. The reason there is no insulation shown in the video is because the blow-out process removes the water, so there's no need for insulation. Other parts of the country, like Texas, might have a cold front dip in from time to time, but never a deep freeze that would require blowing out the sprinklers, and in that case, simply draining the PVB and wrapping the above-ground pipes with insulation will be enough to endure the short cold snap. It just depends on the local climate! Perhaps you can ask your neighbors and local contractors what is done in your area. I hope that helps : ) Thanks for watching, and Happy New Year!

[@baturenko]

Excellent video, thank you! Loved the extra detailed info on the actual CFM vs. manufacturer stated CFM calculations 👍 Question: when you disconnect the air hose from the compressor before switching to the next blowout zone - is it done as an extra precaution or other reasons given that the cutoff valve at the backflow preventer is already in the off position?

[@L35inColorado]

Thanks, and Happy Thanksgiving if you're in the USA! : ) About disconnecting the air hose: I do and show that as a double-redundancy, just to be absolutely certain (and to reiterate) that there's no air applied the system until a zone valve is open. So, it is just "belt and suspenders", so to speak! It's fine to just use the cut-off valve, as long as you're consistent and certain that air is only applied when there's a zone valve open - that's the main concern. I hope that helps - thanks for watching! : )

[@alexroseland9286]

amazing video!

[@L35inColorado]

Thank you, and thanks for watching! : )

[@gil3green]

Nice tutorial, about a day too late for me this year!

[@Ummonchinable]

I would be interested to see you do a video about piggybacking a standalone tank with a compressor to possibly increase CFM. Does that really increase CFM? What is the best way to connect it? Food for thought.

[@mr.j8297]

Very helpful video, learned a lot, what about using pancake compressor of 150 PSI 6 Gallon? Would that work ?

[@L35inColorado]

Thanks! About the pancake - unfortunately, a pancake compressor is just not capable of supplying adequate flow rate (CFM) for the average 10 - 20 GPM residential sprinkler systems because the compressor/motor itself is just too small to displace enough outside per minute to deliver to sprinkler system (CFM), at the required pressure, to hold the sprinklers up for that 1 minute blowout time and get the water displaced. For example, I have two pancake compressors: the older one is a 6 gallon Porter Cable CF2600. Here's a look the insides of that compressor - the motor: kzbin.info/www/bejne/mJeZlGWao6xge9k According to the specs from Porter Cable, that compressor is capable of displacing an intake air mass of 3.7 SCFM @ 40 psi, and 2.6 SCFM at 90 psi. So, at a target blowout pressure of 50 psi, that value would decrease to perhaps about 3.2 SCFM, and then that intake SCFM would translate to just 0.7 actual CFM going to the sprinklers for the blowout at 50 psi regulated. Recalling the "rule of 7.5" mentioned in the video (43:06), such a low CFM would be barely adequate for a sprinkler system of just 5 GPM. Most residential sprinkler systems include zones of about 10 - 20 GPM water delivery. So, the pancakes just can't deliver enough air for an average sprinkler system zone. What some people do with pancake compressors is piggy-back them onto auxiliary/storage tanks. But, adding an aux tanks doesn't increase the ability of the compressor itself to displace more intake air because that "SCFM @ psi" value is a fixed metric based on the cylinder size and electric motor ability. So, since adding an aux tank is not doing anything to increase the compressor motor ability itself, adding the tank doesn't change the "SCFM @ psi" rating. That said - what adding an aux tank can do is increase the initial CFM delivered (flow rate) - as in the air delivered before the compressor motor starts - and on a small sprinkler system, that may be enough to get the job done. Here's this technique in action: kzbin.info/www/bejne/lWScg3p3ia6ehck I think the biggest temptation people encounter when attempting to blowout a sprinkler system with a low SCFM compressor (like a pancake) is that they'll hook everything up, dial the regulator to the correct pressure (say 50 psi), then apply the air and either nothing happens, or the sprinklers heads pop up for a few seconds, then fall back down. In that case, the proper response is to realize that the compressor setup is simply inadequate to supply the required air flow to the sprinklers, and that the solution is to move up to a larger compressor setup (or add an aux tank). But, sometimes people think "I'll just increase the pressure and blast the sprinklers up", so they'll dial up to 90 or 100 psi, recharge the tank, and "blast" the system - not realizing that higher pressure means lower flow rate, and not realizing that they're accidentally working against themselves and increasing the possibility that they might physically damage their sprinkler system components by applying that little burst of very high pressure air to a system that's not designed for such a load. So - that's a long answer! The summary is: technically, yes, you can use a pancake on a very small system - and by "very small" I don't mean a small yard with three sprinklers, I mean something like a super-low GPM drip zone or maybe a system with a single outlet (sprinkler). And again, that's because with a little pancake you're limited to replicating a flow rate that is consistent only with something like a 5 GPM or less zone. If you add an aux tank, you're effective reducing the duty cycle of the compressor since you have more of your "1 minute per zone" period supplied by you stored air, but again the storage itself doesn't increase the CFM delivered by that little motor once tank pressure falls below regulated pressure, and so once tank pressure drops, the regulator is irrelevant because you'll only get the air displace the motor itself can produce. All that is to say - if you have a pancake and small, low-GPM system, you can give it shot and see what happens, but don't be tempted to compensate for flow rate by increasing pressure, because it is physically impossible as they are inverses. Ideally, you want use something capable of delivering adequate CFM, which for most sprinkler systems is likely something close to what's seen in the video. As shown at 49:29 with the compressor reviews, smaller compressors can be used, depending on the systems. But all things being equal - go big, go bad if possible! : ) I hope that helps - thanks for watching!

[@mr.j8297]

@@L35inColorado Thank you for taking the time to write very detailed explanation, I see there are multiple videos on KZbin people doing with just using small pancake compressor. Anyways as you suggested I will give it a try next season. By the way one of your old videos on Sienna spark plug replacement with excellent step by step instructions gave me confidence to do it myself and saved money.

[@L35inColorado]

@@mr.j8297 Nice! Great job on your Sienna spark plug replacement! Blowing out the sprinklers is much easier and more enjoyable than that spark plug job : ) Thanks for watching!

[@juyoung3671]

Thank you so much sharing your experience!! I have a question for you. 24:43 You recommended "Do not supply air to the system until you have a zone open". I have different thought because, in normal case, the water pressure is always there before zone opening. If we assume "air = water", air pressure apply first, then zone open later. Please let me know what I am missing. Thank you.

[@TheDwilliams1000]

Glad you're in Colorado and have the same setup. Unfortunately, I can't make any changes to the system since I rent. Any tips on blowing it out myself?

[@L35inColorado]

The video shows all the steps for blowing-out the system without making any changes. Thanks for watching! : )

[@Ummonchinable]

My system does not have an inlet for blowing out from the sprinkler side of the Febco. FYI, I'd be interested in a video of how you cut the pipe and weld in an air inlet on the sprinkler side of the Febco -- the next time you do that project. I don't have welding experience.

[@patriotlawncare6090]

Couple questions: Why discharge the air between changing zones, what is the difference between 50 psi of air charged at the backflow waiting to go to a zone and 50 psi of water that stays charged there all season? What's with the 45º degree rule on the valves? Some people are saying 45 some are saying leave all the way open, some say there isn't a technical difference.

[@L35inColorado]

Hi - Regarding the reason for isolating/discharging air between the zones: this is a "best-practice" technique to prevent accidentally over-pressurizing the system. Check out this document for more info: www.krain.com/content/files/images/landingpages/winterization/winterizeyoursprinklersystem.pdf Also, as discussed there, the flow of pressurized air is not equivalent to the flow of water because while air and water are both fluids, air is a gas and water is a liquid, and air has a much, much lower viscosity and density. The zone valve closure against pressurized air (instead of water) can apparently have bad effects for some zone valves, so the intentional steps of physically isolating the zone valves from the air compressor are basically like fool-proofing the process to prevent accidental over-pressurization and to eliminate the need for the valves to close against pressured air. Regarding the 45 degree position on the valves: with ball valves (like those on the FEBCO 765), the 45 degree position is the half-open/half-closed point, at which point the valve gate is angled to allow draining without any pockets where water could collect and freeze (water expands when freezing, which can cause the valves to fracture). Here is some more discussion, from a FEBCO document: watersolutionsco.com/userfiles/938/files/WinterizationProcedure.pdf I hope that helps - thanks for watching! : )

[@Ummonchinable]

Awesome video. If one of my zones is a drip line, are there any additional steps to take to blow out that drip line? It seems like the individual emitters in the drip line would impede the flow of water during the blowout.

[@L35inColorado]

Not that I am aware of - we have several drip lines in our system (we have drip lines in three different zones), all of which are downstream of pressure reducers (which is typical for drip lines). No additional steps are required in our system for clearing the drip lines: they are blown-out the same way as the other zones. I hope that helps! Thanks for watching : )

[@Ummonchinable]

@@L35inColorado Thank you! I appreciate you taking the time to answer my question! It gives me peace of mind when I do this myself this year. I don't remember the person I hired in the past to blow out my system doing anything different for my drip line zone either.

[@AaronCook-l7j]

what if i have an electronic pump controller downstream of my PVB? can i send compressed air through this pump?? probably would damage it, no?

[@L35inColorado]

That's a good question, and I don't know the answer, so I'd refer to the manual for the particular pump itself (hopefully it would any notes about "winterization"). Compressed air can cause a pump impeller to spin much faster than the normal water flow causes, so this source below states: "If blowing out your irrigation system with pressurized air, use a narrow box wrench to prevent the shaft from spinning. When the impeller spins too fast, the motor governor can be damaged." www.centraltis.com/news/6-easy-steps-for-pump-winterization/ I hope that helps - good luck! : )

[@adammunoz9]

Installed a new Febco Series 765 Pressure Vacuum Breaker Assembly and can't get it to stop leaking.

[@arhedler]

You might get some help if you can say where it's leaking and/or show pictures.

[@edgerrr]

Outstanding video L35 in Colorado! I'm in Aurora myself. Anyhow, a truly excellent video covering everything a person needs to know in order to properly service/blow-out a sprinkler system. I like how you covered everything from the basics to the minute details. You've obviously paid your dues. 🏔🌄⛰🍂❄🏔...

[@L35inColorado]

Thanks, and thanks for watching! : )

[@glengibson]

Thanks!

[@L35inColorado]

Wow, thank you so much for the Super Thanks! And thanks for watching! : )