When many people think about hydrants, they picture the classic, yellow or red fire hydrant featured in most neighborhoods. However, there’s a whole lot more to a water system than just those quintessential fire hydrants. In order to make sure that all members of a community are getting fresh, clean, and appropriately safe treated water, lots of equipment needs to be in place. The water needs to go through a properly functioning treatment facility, and ultimately end up being delivered to the consumer. A blow-off or flushing hydrant could be the right upgrade for your water system, helping to improve and maintain water quality.
In this blog post, we’re going to explain what exactly a blow-off is, where it’s useful, and the different options you have if you’d like to add these to your system. You should know which type of blow-off or flushing hydrant should work best for you when you reach the end, or at least have a good idea of what your next steps should be. Read on for a complete view of a blow-off or flushing hydrant’s purpose.
Where is a blow-off or flushing hydrant most useful?
Dead-end lines are the ones that need the most attention when it comes to flushing. Treated water that ages needs to be flushed in order to maintain safe residuals for consumers. So, when it comes to many dead-end mains, they need to be flushed out regularly to bring in new, treated water into the line. This helps avoid any issues in water quality for customers. That’s why a blow-off or flushing hydrant’s main purpose is to move aging water out of a system, keeping it fresh and safe for consumers to use.
Professionals in the field have a few options when it comes to accomplishing that flushing. They can open up and flush fire hydrants at the end of those water mains, getting rid of the old water that way. However, if there’s no need for fire protection at the end of a main, and there is no existing fire hydrant, it might be better to install a blow-off or flushing hydrant at that site. That leads us to our next section…
What is a blow-off / flushing hydrant?
A blow-off or flushing hydrant is a device that accomplishes the flushing goals we outlined in the previous section. It doesn’t have the fire protection capabilities as a fire hydrant does, and its primary (sometimes only) function is to flush out old water, especially in dead-end water mains. We’ll go over certain blow-off or flushing hydrant’s expanded purposes in a later section, but for now, just know that these devices are highly specialized and designed to turn over water lines that have water quality issues due to aging water.
Since the primary purpose of a blow-off or flushing hydrant is to flush water out of a system, it is designed toward that end. They feature unique valves, variously sized inlets, variously sized outlets, either a post or box that can be above, below, or at grade, and depending on the model several other features to achieve the goal of flushing. Blow-offs and flushing hydrants are usually 2” or 4” in size and are engineered to turn water lines to improve and maintain water quality, not scour them.
Now that we’re all on the same page as to what a blow-off or flushing hydrant is in the first place, let’s look at why they’re often a good fit for a water system.
What are the benefits of a blow-off or flushing hydrant?
The positives and purposes of a blow-off or flushing hydrant might not seem like a lot at first glance, but they can definitely be game-changers for specific water systems. Here are a few of those benefits:
Low Maintenance
The right blow-off or flushing hydrant doesn’t require much maintenance. And when it does, you can maintain it from above ground without digging. Maintenance usually includes only changing seats and O-rings on a periodic basis dependent upon how often the unit is exercised.
Better Water Quality
We’ve already mentioned how flushing dead-end mains improves and maintains water quality for consumers, but it bears repeating. Installing a blow-off or flushing hydrant in key places is a good strategy for improving a system’s water quality. Regular flushing means keeping chlorine residuals in the safe range and removing aging water before harmful disinfection byproducts can form.
Beats the Alternatives
There are certainly other ways of flushing water through a system to keep the water age low. Many places achieve this through opening regular fire hydrants and letting water out that way. However, those pieces of equipment are not designed specifically for flushing. When using a fire hydrant for flushing, water goes around the plunger where debris in the water may scar the seat, O-rings or do damage to the hydrant in other ways. Many flushing hydrants are engineered with a two-pipe design whereby the plunger moves up and completely out of the way of the flushing water reducing wear and tear on unit itself. A blow-off or flushing hydrant’s design is more closely aligned with flushing.
Cost Savings
If you choose to install a blow-off or flush
ing hydrant instead of a typical fire hydrant, you could be saving as much as half the cost or more. If fire protection is not needed and your purpose is strictly flushing, a blow-off or flushing hydrant means your choice will be much more inexpensive and efficient. While some 2” blow-offs or flushing hydrants can’t flush as much water as a fire hydrant, other 4” flow-off or flushing hydrants absolutely can. Making sure you’re only getting exactly what you need can save your system money.
What types of blow-offs and flushing hydrants does Kupferle make?
If we’ve convinced you that you need to add a blow off water valve to your water system, then you’re in luck. Kupferle has several different options for you to consider. Here, we’ll walk you through them. You can contact us or find a local rep if you need more information or help making a decision, of course, but the following descriptions should be a good place to start.
MainGuard #77
The MainGuard #77 Post Hydrant provides the best in performance and value. Designed and engineered specifically for flushing, the #77 provides excellent flow rates for improving chlorine residual levels and flushing disinfection byproducts (DBPs) to keep water safe for consumers. The unique valve design allows for a full clear-channel flow that is superior to other blow-offs for moving water and passing debris easily. The #77 plunger is also designed to allow for throttling the flow of water while at the same time covering the drain hole to avoid unnecessary erosion. The MainGuard #77 comes standard with all brass principle working parts, 2″ FIP vertical inlet, 2 ½” NST outlet, traffic break-away, and locking security cover. The #77 is self-draining and non-freezing, The MainGuard #77 is fully serviceable from above ground. Certified to NSF/ANSI 372.
MainGuard #78
The MainGuard #78 Blow-Off installs underground in a standard meter box. Designed and engineered specifically for flushing, the #78 provides excellent flow rates for improving chlorine residual levels and flushing disinfection byproducts (DBPs) to keep water safe for consumers. Its unique valve design allows for a full clear-channel flow that is superior to other blow-offs for moving water and passing debris easily. The #78 is also designed to allow for throttling the flow of water while at the same time covering the drain hole to avoid unnecessary erosion. The MainGuard #78 comes standard with all brass principle working parts, a 2″ FIP vertical inlet, a 2 ½” NST outlet, and locking security cover. The #78 is self-draining, non-freezing, and is fully serviceable from above ground. Certified to NSF/ANSI 372.
Eclipse #2
The Eclipse #2 post hydrant has been one of the bestselling flushing hydrants for water main dead ends for over 100 years. Designed for performance and durability, the Eclipse #2 provides excellent flow rates for improving chlorine residual levels and flushing disinfection byproducts (DBPs) to keep water safe for consumers. The Eclipse #2 comes standard with all brass principle working parts, multiple inlet choices up to 4″ MJ, and multiples outlets up to 2½” NST, and is self-draining and non-freezing. The Eclipse #2 is fully serviceable from above ground. Certified to NSF/ANSI 372.
Eclipse #85
The Eclipse #85 Blow-Off Hydrant is designed and engineered specifically for flushing and provides excellent flow rates for improving chlorine residual levels and flushing disinfection byproducts (DBPs) to keep water safe for consumers. The #85 Eclipse Blow-Off Hydrant is designed with a heavy wall cast-iron box. The box sits at ground level and is non-traffic rated. The Eclipse #85 comes standard with all brass principle working parts, multiple inlet choices up to 4″ MJ, and multiples outlets up to 2½” NST, and is self-draining and non-freezing. The Eclipse #85 is fully serviceable from above ground. Certified to NSF/ANSI 372.
MainGuard #7500
The MainGuard #7500 Post Hydrant is designed and engineered specifically for flushing large amounts of water quickly. The unit provides excellent flow rates comparable to a standard fire hydrant. The MainGuard #7500 provides a high flow rate for scouring applications such as unidirectional flushing and the unique valve design allows for flushing of large debris. The unit provides ample flushing velocities usually at half the cost of a fire hydrant. The MainGuard #7500 comes standard with all brass principle working parts, 4” MJ inlet and a 4″ FIP outlet and is self-draining and non-freezing. The MainGuard #7500 is fully serviceable from above ground. Certified to NSF/ANSI 372.
MainGuard #7600
The MainGuard #7600 blow-off installs underground in a meter box and is designed and engineered specifically for flushing large amounts of water quickly. The unit provides excellent flow rates comparable to a standard fire hydrant at half the cost. The MainGuard #7600 blow-off hydrant provides a high flow rate for scouring applications such as unidirectional flushing and the unique valve design allows for flushing of large debris. The MainGuard #7600 comes standard with all brass principle working parts, 4” MJ inlet and 4″ FIP outlet, and is self-draining and non-freezing. The MainGuard #7600 is fully serviceable from above ground. Certified to NSF/ANSI 372.
Truflo #TF500
The Truflo #TF500 Blow-Off is designed and engineered with a slim profile that fits into a standard 5¼” adjustable valve box. The #TF500 provides an alternative to a gate valve, 2” blow-off assembly with two valve boxes and is built for frequent exercising and longevity with minimal maintenance. The #TF500 is cast iron, steel, and brass construction with all brass principle working parts. An all brass option (see photo) is also available. The Truflo #TF500 comes standard with a 2” FIP vertical inlet, and a 2” MIP outlet. The Truflo #TF500 is fully serviceable from above ground. Certified to NSF/ANSI 372.
Truflo #TF550
The Truflo #TF550 Blow-Off is designed and engineered with a slim profile that fits into a standard 5¼” adjustable valve box. The #TF550 provides an alternative to ball valve operated blow-offs, as it utilizes a plunger assembly that is easily maintainable and repairable providing longevity with minimal maintenance. The #TF550 is all brass construction with all brass principle working parts. The Truflo #TF550 comes standard with a 2” FIP vertical straight inlet and a 2” MIP outlet. The Truflo #TF550 is fully serviceable from above ground. Certified to NSF/ANSI 372.
What should you consider when choosing the right blow-off or flush hydrant?
All of the options we’ve detailed thus far are good fits for certain situations, but you need to make sure the functionality and purpose of the blow-off or flushing hydrant fits your specifications.
Perhaps the first criteria you should think about is what you actually need a blow-off or flushing hydrant to do. First, keep your climate top of mind. While most of Kupferle’s blow-offs and flushing hydrants are made for all climates there are a few that are designed for just warm climates. Secondly, determine what flow rate you require. Kupferle blow-offs and flushing hydrants can flush from 380 gpm to up to 1390 gpm (comparable to a fire hydrant). So, knowing the length and diameter of the dead end main can help you choose the right model. Lastly, determine if you want a blow-off / flushing hydrant that is above or below grade. Kupferle offers many of its models in both styles. Below grade blow-offs that can fit into as small as a 5-1/4” valve box or standard meter box to above grade flushing hydrants that resemble a mini-fire hydrant.
Now you know the purpose of a blow-off or flushing hydrant.
Now that you have a better idea of what a blow-off or flushing hydrant does and who it benefits, you should be in a good position to decide whether they might be a good fit for your water system. If you have a dead-end water main that you need to flush regularly, a blow-off or flushing hydrant could be a great solution. They’re easy to service, keep the water fresh and safe for human consumption, and offer a great alternative to traditional fire hydrants for flushing purposes. They cost less than many of your other options, so if there’s a concern about affordability, blow-offs and flushing hydrants could be a solution. Plus, once you’ve installed a blow-off hydrant, it should last for a long time.
Maintaining the appropriate level of chlorine residuals is paramount in keeping water systems safe. Blow-offs and flushing hydrants can help you do that, so if you’re interested, consider upgrading your system. We attempted to answer all of the frequently asked questions surrounding blow-offs and flushing hydrants here, but of course, we can’t anticipate everything you want to know. To that end, feel free to reach out with more things you want to know about the purposes and functionality of both blow-offs and flushing hydrants.