Everything You Need To Know About Backflow Preventers
This article discusses how backflow preventers, such as the Conbraco 4A-500 Freeze Resistant PVB Backflow Preventer, are the heroes of your sprinkler system. Sprinkler systems are not very complicated. They deliver water to plants and vegetation alike in a uniform and controlled manner. While designs can vary in size and complexity there are a few parts that every sprinkler systems have in common. These variations are based on the irrigation needs of the property and the local legal regulations among other things.
This part goes unnoticed because of its passive role in the otherwise regimented and choreographed lawn watering production. The corps of valves open and close in perfect conformity with the system controller. However, the backflow preventer performs its task consistently and dutifully.
This device is the only non-electronic part of the sprinkler system which is constantly working day or night. It works whether or not your sprinklers are running.
Types Of Backflow Devices:
- Pressure Vacuum Breakers (PVB)
- Double Check Assemblies (DCA)
- Reduced Pressure Zone Assemblies (RPZ)
- Atmospheric Vacuum Breakers (AVB)
So What Makes The Backflow Preventer So Special?
When you go get a glass of water straight from the tap, do you worry about it being contaminated? Or even think twice before you drink it? I suspect the answer is, “No.” Most likely because so many of us grew up being conditioned to not worry about things like water contamination. Should you worry?
After all, it is not uncommon for farmers to apply chemicals or fertilizer through their irrigation systems. It is possible that some of that fertilizer could be siphoned back through the pipes contaminating the potable drinking water we all use.
The image below shows an example of a backflow preventer. This one is the Febco 765 3/4″ PVB Backflow Preventer available at Sprinkler Warehouse.
No, You Don’t Need To Worry
Fortunately, backflow preventers are an integral and requisite part of nearly all irrigation installations. They can be found throughout the public water system. So, the answer is: “No, you do not need to be on a constant alert for contaminated water.”
There are several kinds of backflow preventer designs in use today. They range from simple to complex designs incorporating multiple fail-safes for protection. To put it very simply, a backflow preventer is an elaborate one-way valve. It allows for water to flow in one direction into a system but will prevent any water from returning back into the potable water source.
“My water comes from a well on my own land. Do I need a backflow preventer?”
You will have one whether you get your water from the city water supply or your own on-site well. They are generally located on your private property as close to the potable water supply source as is possible.
Get Your Backflow Device Tested By A Professional
If you are not already familiar with what a backflow protector does, you should contact a local backflow testing service. They will come and test your backflow preventer. It is recommended (and in many places required) that you have your device tested yearly by a certified tester. They will be able to show you the location of your preventer. The tester will tell you what style and brand of device you own. They will test it using special tools and provide you with results. (I was able to find local listings for testing services online in several large and small towns by typing “backflow preventer testing [and your town name]” into Google. I found the average cost to be in the $75-85 range for a residential inspection/testing nationwide.
Backflow preventers are designed with multiple fail-safe features to protect and ensure their function. However, there are two very serious, very real, threats facing backflow preventers:
Theft & Freeze Damage For Backflow Devices
Backflow preventers are a prime target for theft because they are made from valuable metals. With the replacement cost being as high as $500+ it is important that you take proper precautions to prevent theft. Do this by incorporating an anti-theft device with your backflow preventer. An example of this is a backflow theft prevention cage or the Sekure-It lock-up kit. For less than the cost of one replacement backflow preventer, you can ensure your backflow preventer stays protected.
The other fatal factor to be aware of is cold weather. If you live somewhere in the country where freezing temperatures are a common occurrence, you should winterize your sprinkler system. This includes the backflow preventer. Regardless of where you live in the country, it is recommended that you insulate your backflow preventer. You should also insulate any other exposed pipes or fixtures to protect them from frequent or infrequent cold temperatures. The complete guide on winterization can be found here.
Thermostatic Freeze Relief Valves
Thermostatic freeze relief valves are now available to add to your backflow preventer or climate-exposed pipes. It will automatically open itself up, permitting an escape from the pressure created by frozen water. For less than $100 this kind of relief valve will prevent a cracked backflow preventer. You will be saving money in parts and labor.
Of course, you can always take your cracked and broken backflow preventer down to the metal recycles. Then get enough money to hopefully buy a relief valve to install on the next one.