How To Protect Your Backflow Preventer From Freezing

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"Steve and Co. did excellent work in fixing and improving our sprinkler valve system in a very timely manner. Would definitely recommend to others. Thanks!"

Kyle R.
(Taken from a review on our Facebook page on 06/18/2016)

"We had a backflow in such bad shape it was less expensive to replace it than fix all the broken parts individually. The Maintenance Shop picked up a new one and installed it in about an hour"

David W. Boise, Idaho on 08/15/2016)

"I found out from Steve we had a unit on the sprinkler system of the home we had just purchased in Eagle that was not legal and couldn't be blown out so he replaced it with another backflow unit and then blew out our sprinklers like he had done before for several years at our other home."

Stephanie R., Eagle, Idaho 04/10/2016

Backflow Preventer Winterization

Why Homeowners Should Winterize Their Backflow Preventers When Possible

The Maintenance Shop winterizes backflow preventers during our sprinkler blowout at each property, but there are reasons why we advise homeowners to prepare their backflows themselves if at all possible before we get there.

There are over 200,000 homes, businesses, farms, etc., in the Treasure Valley that need their sprinklers Looking For A Sprinkler Blowout?blown out each fall, and with all continued growth in the valley that number is going to steadily rise. In 2017 there were 5,195 building permits issued in Ada and Canyon county combined. Unfortunately, there are not enough QUALIFIED sprinkler blowout technicians to meet this demand, which is why some homeowners find they are wating up to 3 weeks for a sprinkler blowout. We put emphasis on "QUALIFIED" technician because every spring we get a heavy workload doing repairs on systems from previous season sprinkler blowouts being done by those out to make a lot of quick cash that don't know what they are doing, and then can't be found again. Nearly half of these repairs are damaged backflow preventers because the technician either didn't follow the steps we are going to show you below, or didn't do it properly. They are able to do this because of the high demand and lack of technicians. Out of desperation homeowners will flag someone down pulling a compressor down their street, or call a number on a sign posted on a street corner without really finding out who they are. ALWAYS ask who they work for, and if they are licensed or work for a licensed company.

The weather here in the valley is unpredictable to say the least. Underground sprinkler systems are usually quite safe even into early or mid December if we haven't had several days of extreme cold temperatures in the teens. Sometimes even into January. We have proven that several times doing sprinkler blowouts when the outside temperature was 13 degrees with snow on the ground, but the ground temperature itself was in the mid 30's. Snow is actually a great insulator. HOWEVER, backflow preventers, ESPECIALLY ones that are above ground will not fair well even if the temperature gets down to the mid 20's and stays there for several hours. A slow drop to freezing won't be a problem, but a continual drop that stays there for awhile could cause a backflow preventer to freeze and crack.

The older backflow preventers are comprised of lead and brass, whick will expand some in the cold before cracking. The newer lead-free ones are more fragile. With the rising replacement cost of backflow preventers, and especially since Double Check Backflow Preventers can no longer be installed on sprinkler systems in Idaho, we need to protect our current backflow preventers the best we can.

You Can Easily Winterize Your Backflow Preventer To Protect It From Freezing

We suggest you winterize your backflow preventer as soon as you are finished watering for the season. Don't put it off until it starts gettting colder. You will have no use for it again until Spring.

The procedures we have put together below are exactly what we do when we come to your home to blow out your sprinkler system. The steps are easy to follow, and not only will it give you piece of mind, but it will actually save us valuable time. If you choose to winterize your backflow yourself, we will always check it during the sprinkler blowout to make sure it was done correctly, however, please follow the directions carefully to make sure no damage occurs.

Backflow Preventer Winterization Instructions

Look at the images below and choose the picture that best matches the backflow preventer you own. There are different varieties, but most look similar to each other. The PVB's and RP's will always be above ground, and the majority of the time the DC's will be below ground, although on rare occassions we have found them above ground. Click on the picture and it will open in another screen to full size where you can print the image. We suggest you put the instructions next to your timer where you have easy access to it when you need it.


NOTE: If you do not know the difference between the main and drain valves, try turning one valve counter-clockwise. If water starts coming out it is the drain. If it doesn't move, it is the main. Shut the main valve by turning clockwise, and then open the drain by turning counter-clockwise.


(If you have trouble physically being able to carry out any of the instructions below please enlist the help of a family member or neighbor)


PVB Backflow Assembly Winterization

Pressure Vacuum Breaker (PVB) Winterization Instructions

Double Check Valve Assembly Backflow Device Winterization

Double Check Valve Assembly (DC) Winterization Instructions

Reduced Pressure Backflow Assembly Winterization

Reduced Pressure Principle Backflow Assembly (RP) Winterization Instructions

Pump Winterization Instructions

Pump Winterization Instructions

filter winterize instructions

Irrigation Filter Winterization

Valve Pressure Relief

Electronic Valves Pressure Relief