EXCEL 10 FCU CONTROLLER LNS PLUG-INS USER GUIDE

Control Application

Fan coil unit systems in commercial buildings control room temperature through the control of heat and/or cold water valves and fan speed. Electric reheat coils may also be used in the system. The Excel 10 FCU Controller is located in the FCU and is typically connected to an Excel 10 wall module

which incorporates a temperature sensor, setpoint and fan speed controls, and a bypass or override button. Fig. 2 shows a typical FCU ontrol application.

 

window

 

contact

e.g. Excel 10 W7754

 

FCU Controller

 

Honeywell

Excel 10

D-71101 Schönaich

 

Made in Germany

 

 

wall module

LonWorks network

Fig. 2. Typical Fan Coil Unit control application

Control Provided

Excel 10 FCU Controllers provide room temperature control for two- and four-pipe fan coil units with optional electric heating coil. The basic control sequence is shown in Fig. 3. As space temperature falls below the heating setpoint, the heating output is increased. As space temperature increases above the cooling setpoint, the cooling output is modulated to 100%. Switching levels for staged heating/cooling and fan speeds are configurable. The fan may still be configured to run continuously during the zero energy band in the "occupied" mode. Additional configurable fan control features include fan minimum ON/OFF times, run-up, and overrun-times.

Excel 10 FCU Controllers use a PID control algorithm in which each of the three parameters can be configured. There are additional configurable boost parameters ("PID Boost:" "Cooling" and "Heating") which specify a range outside of which the heating or cooling outputs are turned ON fully for faster response (in the case of thermal actuators, this specifies the control hysteresis). The controllers are delivered with factory defaults for each of the parameters.

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EN2B-0285GE51 R0909

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Honeywell W7752D specifications Control Application, Control Provided

W7752D specifications

The Honeywell W7752D is a versatile and advanced electronic gas combination control designed primarily for use in commercial heating systems. This product stands out for its ability to manage both gas ignition and safety functions, which are critical for maintaining the efficiency and safety of heating appliances. Its robust construction and advanced features make it a popular choice for HVAC professionals and service technicians.

One of the main features of the W7752D is its integration of multiple functions in a single device. It serves as both an automatic gas ignition control and a safety shut-off valve, which simplifies installation and reduces the need for additional components. This integrated design not only enhances reliability but also streamlines maintenance procedures.

Another notable technology utilized in the W7752D is its microprocessor-based control logic. This advanced technology allows for precise management of the ignition sequence, improving the overall efficiency of the heating system. The microprocessor enables the control to adapt to varying operating conditions, ensuring optimal performance even under changing demands.

The W7752D is equipped with features that enhance user-interface and diagnostics capabilities. It includes LED indicators that provide clear information about the operational status and any potential issues. This diagnostics capability facilitates easier troubleshooting, saving time and reducing the likelihood of extended downtimes.

Safety is a primary concern in gas appliances, and the W7752D addresses this with built-in safety mechanisms, including flame detection technologies. These features ensure that the appliance operates safely, automatically shutting down in case of any irregularities during operation. This emphasis on safety not only protects property but also provides peace of mind for users.

In terms of compatibility, the Honeywell W7752D is designed to work with a wide range of gas heating appliances. Its flexibility allows it to be used in various applications, making it suitable for different types of commercial environments. Additionally, the control complies with relevant safety and performance standards, ensuring reliable operation.

In summary, the Honeywell W7752D combines advanced technology with essential safety features, making it a top choice for commercial heating applications. Its integrated design, microprocessor-based control, user-friendly diagnostics, and robust safety mechanisms make it an essential component for efficient and safe gas heating systems. Whether it is for new installations or replacements, the W7752D provides HVAC professionals with the reliability and ease of use they demand.