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Home > Backflow > Winterizing Your PVB

A Guide To Winterizing Your PVB

Hi, Alfred Castillo here – Sprinkler Warehouse Pro. Today I’m going to share with you how to actually winterize a backflow preventer.

Keep Your Valves In Line

As it’s currently in its state, you can see that both of my valves are in the open position. We have supply going into the backflow preventer, out to the outlet, and into the valves. This is normally the way your sprinkler system will operate. For the winter is where we have to take a little bit of extra measures here to prevent any kind of failures of that in this backflow. As the supply runs up into the pressure vacuum breaker, we want to go ahead and turn this valve that’s currently on. You know they’re on, in the direction of the pipe. So, if it’s parallel to the pipe—they are on. We’re gonna end up turning this particular valve, off. We want to ensure that any water that might be in this particular PVB has the opportunity to expand without breaking the valve or the cap. So, what we’ll do is we’re going to do is release—relieve the pressure from what we call here—these bleed valves, or these cock stops.

Right now, they are in a closed position. As you can see here, they’re perpendicular with the actual valve itself. We want to go ahead and release these bleed valves if you can turn them right now. That’s closed. These ball valves are not a screw. All these are just real simple ball valves that rotate. So, if I open, this is closed. Open. Closed. It’s not a screw, so right now that’s closed. Again, in the winterization of this particular backflow preventer, we always want to keep them open there so any expansion of water will actually flush out over here.

Prepare The Insulation For Harsh Weather

The next step to make this particular winterization more effective is to go ahead and utilize insulation. I have a couple of pieces here that I’ve pre-cut just for the sake of this video, but we’ll actually go ahead, and you can pick this particular installation up at Sprinkler Warehouse. So, what we’re going to end up doing is we’re going to insulate the supply side first. Now one of the important things that we want to point out when we’re insulating the supply side. Many times, homeowners will only insulate up to the actual valve itself, or up to the brass part, and that’s where a lot of homeowners make mistakes – they do not want to insulate, or they don’t, or they fail to recognize that insulating this particular valve is just as critical.

Why is that? As you can see here on this particular valve, it’s actually the same one that’s right in here. I have it open. This is actually in its open position where water flows. You can see here. If you can see right there, water flows right in through here. Well, when it closes you can see the stainless ball valve that it is. In here it opens and closes. When you close this, we actually have water that is still in that ball valve, and part of that water essentially is just resting now on the sides of the valve itself. If we don’t properly insulate this part, you can see what might happen in the event of a hard freeze—that water will expand. And you’ll get a—it’s not really a hairline crack. You can see it’s a pretty good-sized crack, and this is brass my friends.

This is just what a little water can do if we don’t properly insulate that. That’s going to be really key and important to know. When insulating and winterizing your PVB, your backflow preventer. It’s important to go ahead and insulate all the way to the actual PVB itself. You’ll see here, I’ll make the measurements. You can make the cuts using the insulation. And we’re going to go ahead and insulate all the way up. To pretty much where the PVB starts. So, we have the valve insulated. You actually also have the PVC pipe insulated. Again, our knob is in its off position here. Sometimes these knobs will actually rust out and go bad. We also have a kit here where you can actually buy these particular valves right here at the Sprinkler Warehouse made out of stainless steel. So, you don’t really have to worry about rust or anything like that.

How To Insulate Your PVB

Once we have this pre-cut and trimmed, let’s insulate. You can go ahead and get some tape. Now you want to go ahead and try to insulate as much of this particular valve as possible.  

So, as you can see here. It’s closed pretty well. I can close that up. When I tighten it up. You want to see if you can cover up any exposed part. So, what we’ll end up doing is—I’ll go ahead, and you know—if there’s any excess insulation here. You can go ahead and tape. And just kind of measure out what you need to cut out. There it’s a little square there. I’m just going to go ahead and try to fill that gap. With um—with a particular little bit of insulation. I can close this, and then we’ll have an effect. Actually, there’s probably a little bit more here.  Make it good, conform there—there we go. And then we can go ahead and have a very nice tight fit.

The important thing is you want to make sure that every part of this valve is insulated. With that, we have this particular insulation tape that you can also pick up here at Sprinkler Warehouse. And then we’ll just go ahead and start insulating from the top. It’s important to ensure that we have a good tight fit around there. You want to wrap it around a couple of times to ensure that you don’t have any kind of exposure and to make sure you do have a tight seal around it. And I’m going to go ahead and wrap it around a couple of times. I’m gonna do a little overlap here. Just to ensure that I do have it completely covered, I’ll go ahead and make a nice cut here.

Where it is, it’s got a little bit exposed there, but no problem. You just continue to wrap it around if need be – it’s okay. And at least with this now, if any water is building up in this particular valve as a result of the closure, with it being properly insulated, you really don’t have to worry now about any type of rupture. The important thing is to insulate the supply side, but it’s also a good idea to insulate the side that actually will go to your valve. And so, by doing that again you can go ahead and measure. Measure some insulation. We want to do the same thing as well. We want to not only measure the actual PVC pipe. But we want to measure the insulation to cover over the actual valve itself. For very similar reasons as we’re covering the supply side valve. We want to cover the outlet valve as well.

So, what we’ll do is, we will also go ahead and continue to wrap up this side here. Once you get the measurement, you want to go ahead and go all the way to the PBV. We’re going to go ahead and get this covered. We also want to see if we can get a good little insulation to cover every part of that valve as possible. Slowly I’ll make my way there’s probably another little exposure there that I’ll go ahead and address to make sure it is completely covered, then I can go ahead and insulate the rest of the pipe. While accommodating it, I might have to just snake it in a little bit here to make sure that I got a good wrap-around. Then I’ll just continue wrapping the rest of this particular pipe, this side as needed. You can go ahead and finish that off, properly insulating it.

So, there you have it, my friends. Now you have the proper winterization technique of a backflow preventer on how to make this winterize with the proper positions on your valves – on your actual valves, which is supposed to be closed, and this is open – and the proper way to insulate a backflow preventer.

Feel free to leave a comment. And let us know what other subjects you are interested in learning about. So, again Alfred Castillo here from Sprinkler Warehouse.

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