Most people are familiar with pressure valves and how they work. Probably because almost everyone has been in a shower when someone else in the house has flushed a toilet. You know the drill. The water gets very hot very fast, and you either jump out of the shower or hug the shower wall avoiding the hot drops until the pressure balances again.
While a pressure valve will help eliminate that particular problem, we’re missing the point if we only focus on pressure.
What Are Thermostatic Control Valves?
The purpose of a control valve is to control setpoint temperature. A pressure balance shower valve addresses temperature flux only due to inlet pressure changes. You’ve addressed only one potential, indirect risk. There are some, albeit rare, circumstances, such as simultaneously occurring changes in inlet temperature and pressure, where a pressure valve could expose a bather to greater danger. A direct response to output temperature changes is the only way to provide the highest level of bather safety.
The best solution is a thermostatic control valve. A thermostatic control valve prevents dangerously high output temperature regardless of input and outlet variations and demand variations.
If there is a failure in the cold water supply for any reason, the sensor will effectively shut down the flow of hot water to prevent scalding. If a failure occurs in the hot water supply, the sensor will effectively shut down the flow of cold water to prevent thermal shock. Any spike in temperature, whether hot or cold, will be addressed almost instantly.
For an added level of safety Acorn Controls lavatory and group shower valves; which do not allow for user control, come factory set with a setpoint at 105 degrees. While the installer can make adjustments to the setpoint, the factory set is to help prevent an unsafe maximum bath temperature. Even if the installer forgets to check and/or adjust it.
Is safety really as big a concern as people make it out to be?
Safety is a concern to all plumbers and contractors but commercial plumbing engineers and contractors have the health and safety of high numbers of people to consider with every building.
Legionella: Even with all we know about Legionella, advice is still out there recommending that home owners and installers turn down the temperature on water heaters to prevent scalding and save energy.
This is dangerous advice. Water stored at below 140 degrees is susceptible to growing Legionella bacteria, which is responsible for a bacterial pneumonia known as Legionnaire’s Disease.
No one wants the liability of a breakout of Legionnaire’s Disease in a dormitory or hotel, let alone in a healthcare facility.
Scalding: What you consider a comfortable temperature might be unbearable to someone else. Everyone has his or her own pain threshold. But you know this, and that’s why, when you run the hot water in your sink and shower, you tentatively test it with a quick swipe of your hand.
Personal preference aside, consider that at a temperature of 133 degrees, a child or elderly person’s skin can develop 3rd degree burns in 15 seconds. At 140 degrees, it takes just 5 seconds.
Thermal Shock: Thermal shock is the body’s reaction to a sudden change in water temperature, be it hot or cold. A blast of cold water might not just make you grumpy.
Often, even if suddenly blasted with cold water in a shower, the bather will quickly try to jump out of the way. This can be a dangerous situation and can cause serious injury due to slip and fall.
You certainly do not want the liability for any of these safety risks resting on you. Especially when installing a thermostatic device will solve the problem safely.
Water Savings Are An Added Bonus.
Acorn Controls thermostatic-only solutions save water. Thermostatic valves automatically draw only from the hot water supply until cold water is actually needed for the desired temperature.
Because Pressure Balance shower valves and mechanical mixers have no automatic limitation of the cold water supply, they not only waste cold water but also slow the draw of hot water, causing a longer wait for the valve to reach the desired setpoint.
In high use facilities, such as hotels, hospitals and universities, you’re looking at savings of thousands of gallons of water a year. Savings, as significant as these, will certainly help with your LEED certifications.
Cost Is No Longer An Issue.
At one time combo or dual certified valves were significantly more expensive than the simple pressure valve. That is because they had both a pressure mechanism and a temperature control built into them making those valves more expensive to manufacture.
That is not the case anymore with Acorn Controls thermostatic-only solutions. We’ve eliminated the need for two mechanisms. Our thermostatic control valves do both jobs with one sensor. They require fewer materials, so they are less expensive to manufacture. Those savings are passed on to the customer.
Now you have the ability to significantly improve the safety of individuals and reduce water consumption for just a few cents more.
When choosing a control valve for your building project, be sure to reduce your own risk by choosing a thermostatic control valve that meets the latest ASSE standards. For example, many shower valves that are dual certified T/P as of this date have yet to re-certify and confirm that they are capable of meeting the latest, more stringent version of the ASSE 1016 standard and maintain their T/P certification.
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