Flood Protection Valve

By November 17, 2021Uncategorized

Rain isn’t the only way a building can flood. If there are Domestic or Fire Water Storage Tanks in the building, a flooding risk is always present.

Cougar Systems Level Controls constantly monitor for High Level and actuate a motorized valve to shut off the water supply to prevent overfilling the tank and flooding the space. 

Flood Protection Valve Tech Talk Transcript:

Hi, I’m Tim, Zacharias with Cougar USA. In this Tech Talk, we will cover flood protection valves for fill stations and atmosphere storage tanks. In the city of Houston, we have the requirement to go through the atmosphere storage tank before we add booster pumps into our building. So, a lot of these are going to be installed on the first floor, maybe in a basement on a vault outside, and we want to prevent those tanks from overflowing and flooding the building.

In order to do that, we have level sensing devices in the tank there sending that level read out to the level control panel like this. We use a motorized butterfly valve Upstream of our fill valves as our Safeguard to prevent the tank from overflowing and flooding the room.

So we have the high-level alarm set based on the height of the tank in inches, and once that level is reached, it’s going to signal the high-level alarm, as well as trigger the block valve. Now the block valve is going to stay closed until the tank level is drawn down, and then it will reset the high-level alarm, open up the block valve, and if one of the fill valves has failed and is still allowing water in the tank, it will refill and hit that high-level alarm again and trigger the block valve to close, so, your block valve will essentially act as a backup fill valve, but it’s going to trigger that high-level alarm every time which is one of the reasons we definitely recommend monitoring that high-level alarm with the building automation so that they can get those alarms and that feedback that the block valve is on. So we prefer using the butterfly valve with the motorized operator for those two reasons,

The other alternative is to use an electronic Cla-Val like this one 3601 that we use for the fill valve. This makes a great fill valve because we have constant or regular flow through the valve, through the fittings, in the solenoid that keeps them clear of trash and debris and allows for that diaphragm to load and unload every time.

So if we have one of these solenoid valves, this 1-3601, as the block valve, it’s going to sit in the open position most of the time, and it’s going to have water flow through the body of the valve, but not necessarily through the tubing and through the solenoid. So, you could have trash build-up on the solenoid or somewhere in the strainer there, or anywhere else in the pilot, things like that. So when you do get the high-level arm, and you do need to close it, this valve will send power to the solenoid, which is going to try to open up and load water onto the diaphragm to close it.

Now, if water can’t get into the tubing or through the pilot, that’s not gonna let water on the diaphragm and allow it to close. The other issue we would have is that the solenoid valve requires constant power, in this case, 120 volts to hold the valve closed. So if we had a loss of power or an issue with the control panel or even if the solenoid failed. Any one of those three, you would lose power to the solenoid and the valve would go back to its normally open position, and then you would overfill your tank. With the motor-operated valve, the butterfly valve can sit for long periods and not have the issue of being able to close because it’s been sitting open for long periods. Also, with the motorized actuator here, we send one signal from the control panel to open the valve and a separate signal to close the valve. Once it is in the open or closed position, it will stay there until we send the second signal to move again. So we’re only sending a signal to move the operator, not to hold it in the open or closed position.

If you have any other questions about the flood valve or the flood protection valve and why we’ve gone with the butterfly valve in the motorized actuator, please feel free to reach out or check out other Tech Talk videos for more information.

Thanks.

Cougar USA has worked in hundreds of buildings in Houston with break tanks, level controls, and booster systems. For more information or a free building assessment, contact us here.