3)Low Temperature Systems - Some systems, such as radiant tubing systems, require the system water temperature to be limited to a value below the temperature of the water leaving the TWZ. These systems also typically have return temperatures well below the 120°F minimum.

Figure 13 illustrates the use of a heat exchanger to connect the TWZ boiler to this type of system. The heat exchanger will permit the transfer of heat from the boiler water to the low temperature system while holding the system supply and boiler return temperatures within their limits. For this system to work properly, the heat exchanger must be properly sized and the correct flow rates are required on either side of the heat exchanger. Consult the heat exchanger manufacturer for sizing information. The water in the boiler is completely isolated from the water in the system. This means that separate fill and expansion tanks are required for the heating system loop.

There are several other ways to connect low temperature systems to the non-condensing boilers like the TWZ such as four way mixing valves and variable speed injection pumping systems.

4)Systems containing oxygen - Many hydronic systems contain enough dissolved oxygen to cause severe corrosion damage to a cast iron boiler such as the TWZ. Some examples include:

•Radiant systems that employ tubing without an oxygen barrier.

•Systems with routine additions of fresh water.

•Systems which are open to the atmosphere.

If the boiler is to be used in such a system, it must be separated from the oxygenated water being heated with a heat exchanger as shown in Figure 13.

Consult the heat exchanger manufacturer for proper heat exchanger sizing as well as flow and temperature requirements. All components on the oxygenated side of the heat exchanger, such as the pump and expansion tank, must be designed for use in oxygenated water.

5)Air Handlers - Where the boiler is connected to air handlers through which refrigerated air passes, use flow control valves in the boiler piping or other automatic means to prevent gravity circulation during the cooling cycle.

FIGURE 13: ISOLATION OF BOILER FROM SYSTEM

WITH A HEAT EXCHANGER

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Crown Boiler TWZ100, TWZ200, TWZ090, TWZ125, TWZ065, TWZ175, TWZ150, TWZ120, TWZ075 Isolation of Boiler from System
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TWZ150, TWZ125, TWZ065, TWZ075, TWZ100 specifications

Crown Boiler, known for its solid and reliable heating solutions, has designed the TWZ series to provide effective heating for both residential and commercial applications. The models in this series—TWZ090, TWZ120, TWZ175, TWZ200, and TWZ100—offer varying capacities and features tailored to meet diverse heating needs.

One of the key features of the TWZ series is its efficiency. These boilers are designed with a cast-iron heat exchanger that maximizes thermal efficiency, allowing for optimal heat transfer. This not only helps in reducing energy consumption but also ensures that the home remains warm and comfortable during the colder months. With an annual fuel utilization efficiency (AFUE) rating that can reach up to 85%, users can expect lower energy bills as well.

Each model in the TWZ series is equipped with a durable and robust construction. The cast iron sections provide increased resistance to wear and tear, making the TWZ series a long-lasting solution for heating needs. This is particularly beneficial for users looking for reliability over time, as the longevity of these boilers reduces the need for frequent replacements.

In terms of technology, the TWZ series features advanced controls that enhance functionality and ease of use. These boilers are compatible with various heating control systems, allowing users to fine-tune their heating setup according to their specific requirements. The inclusion of a flame safeguard system further ensures safety during operation, reducing the risk of malfunctions and improving overall reliability.

The TWZ series is designed for easy installation and maintenance. With options for direct venting or conventional chimney venting, homeowners and installers can choose the most suitable configuration for their properties. Additionally, the maintenance access points on these boilers make routine service checks simple and efficient, ensuring that the boilers remain in optimal condition.

Another important characteristic of the Crown Boiler TWZ series is its quiet operation. Advanced engineering minimizes noise production, making these boilers ideal for residential settings where peace and comfort are valuable.

In conclusion, the Crown Boiler TWZ090, TWZ120, TWZ175, TWZ200, and TWZ100 models offer a compelling combination of efficiency, durability, advanced technology, and user-friendly features. Whether for residential or light commercial use, they represent an excellent choice for anyone seeking reliable heating solutions.
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