What’s the Hype with Thermostatic Balancing Valves
Hot water distribution systems are critical to plumbing design, especially in large residential and commercial buildings. Maintaining consistent hot water temperatures across these systems can be challenging, but thermostatic balancing valves have emerged as an innovative solution.
What Are Thermostatic Balancing Valves?
A thermostatic balancing valve is a dynamic device that automatically adjusts water flow in response to temperature changes within a domestic hot water system (DHWS). Unlike manual balancing valves, which maintain a set position, thermostatic valves continuously adapt to real-time conditions, optimizing water flow without manual intervention. These valves rely solely on sensing temperature to maintain a set temperature in the water lines instead of using pressure or flow calculations. It is a temperature device solving a temperature problem.
By ensuring hot water is distributed evenly throughout the system, thermostatic balancing valves improve energy efficiency, minimize water waste, reduce maintenance needs, and provide hot water on demand.
Why is Balancing a DHWS Necessary?
In any hot water recirculation system, water naturally flows through the path of least resistance. This often leads to uneven distribution, where branches or risers located farther from the hot water source experience reduced flow and significant heat loss.
Balancing valves counteract these issues by normalizing water flow throughout the system. Installed at the end of the branch or the top of each riser, these valves ensure sufficient flow and temperature in every branch or riser to offset the heat loss.
Typically, the branches/risers closest to the water source require the least flow, and the ones further away require more.
Types of Balancing Valves Used Today
Several balancing valves are available today, each with its advantages and disadvantages.
Manual Balancing Valves
Manual balancing valves have traditionally been used in DHWS. They are an adjustable ball valve type with pressure ports used to determine the flow. While functional and inexpensive, they require iterative adjustment to balance DHWS because they are pressure-dependent flow devices. Every time a manual balancing valve is adjusted, it impacts the setting of all the other valves in the system. This process can be time-consuming and expensive, especially in larger systems, and often requires a journeyman or certified plumber to balance the system.
Fixed Flow Balancing Valves
Also known as pressure-independent or automatic balancing valves, these devices have a constant flow rate based on a customer-selected cartridge. They utilize replaceable, flow-regulating cartridges, each with a set operating flow rate and differential pressure ranges, eliminating labor associated with manual balancing. Fixed flow valves have static flow settings and are not dynamic, meaning they do not adjust the flow as conditions change within a system.
Due to their small orifices and tight clearances, they are also prone to clogging in high mineral-content environments.
Electric Balancing Valves
Electric valves offer temperature sensing, motorized control, and integration with a building management system (BMS). While they provide advanced control and data monitoring, these valves are complex, expensive, and less reliable due to their intricate components. The use of these valves in DHWS has been minimal.
Thermostatic Balancing Valves
Thermostatic valves dynamically adjust flow based on real-time temperature changes. By sensing the water temperature, they automatically modulate flow to maintain a set temperature in the branch or riser, eliminating the need for manual calculations and adjustments. This technology ensures quick and accurate system balancing.
How Thermal Balancing Valves Operate
Thermostatic balancing valves are gaining attention due to their ability to automatically regulate water temperatures in domestic hot water systems – eliminating manual balancing and callbacks.
Thermal balancing valves use paraffin wax actuators to modulate flow based on fluid temperature. A temperature increase changes the wax state from solid to liquid, creating a maximum change in volume. The wax pushes on the diaphragm and extends a piston to adjust the amount of flow through the valve. As the temperature cools, the wax returns to a solid, and the piston retracts, allowing for more flow. This simple, reliable mechanism enables precise temperature control.
Key Advantages Include:
- No manual intervention: The valves adjust automatically as system conditions change.
- Energy efficiency: Consistent temperature control reduces heat loss and water waste.
- Reliable operation: The wax-based actuator has no shelf life and ensures long-term durability.
- Pump protection: Valves never fully close, ensuring adequate flow to prevent pump overheating.
Fixed vs. Adjustable Thermostatic Valves
Fixed Thermostatic Valves
Fixed thermostatic balancing valves are factory-calibrated for a specific temperature and cannot be adjusted in the field. A replacement kit can quickly change the actuator’s temperature set point, but they are set for a given return temperature. This tamper-proof design eliminates the risk of adjustment by non-qualified personnel and ensures consistent performance.
Fixed thermostatic balancing valves have a higher Cv than adjustable valves at 5°F below their set point because they go from fully extended to retracted over a 10°F lifespan vs. 50°F for the adjustable thermostatic balancing valves. With a broader stroke range and higher Cv, fixed thermostatic balancing valves minimize pressure drops and simplify installation.
Adjustable Thermostatic Valves
Adjustable thermostatic balancing valves have an actuator cartridge design that allows users to set the desired temperature by adjusting the position of the actuator. The temperature range is typically over a 50°F span. They have low Cv at 5°F below the desired return temperature, resulting in higher pressure drops than fixed valves (>4:1).
While versatile, these valves require calibration during installation, which introduces potential errors if some valves are set incorrectly in the system, making troubleshooting difficult.
Why Choose CircuitSolver® Thermostatic Balancing Valves?
For over a decade, CircuitSolver® thermostatic balancing valves have transformed domestic hot water recirculating system balancing. By automatically and continuously adjusting to maintain the specified water temperature, CircuitSolver® eliminates the labor-intensive process of manual balancing. It is a temperature device solving a temperature problem—not a flow device trying to solve a temperature problem.
Key Benefits Include:
- Reliable performance: CircuitSolver® addresses temperature problems directly, ensuring even hot water distribution.
- Ease of installation: Ideal for both new construction and retrofits, these valves simplify system balancing without requiring balancing.
- Reduced callbacks: Automatically balancing the system resolves common hot water issues, eliminating the need to have a professional balance the system.
With thousands of successful installations, CircuitSolver® thermostatic hot water recirculation valves are a trusted solution for plumbing engineers and contractors seeking efficiency and reliability.
Ready to optimize your next plumbing project? Contact CircuitSolver® to learn more about our thermostatic balancing valves and how they can simplify your DHWS design.
Watch the video to learn more about thermostatic balancing valves.