shutoff valve. Remove the front and right-side panels from the unit. Disconnect the union between the valve body and the blower. Label the four pressure tubes that are connected to the valve actuator, to ensure that they will be replaced correctly. Remove the valve actuator, per the instructions above. Unscrew the valve body from the gas train. After the valve has been removed, replace with a new valve in the reverse order. Turn on gas shutoff valve and 120 volt power and check appliance operation and tightness of gas valve connections.
7.2.4Safety Gas Valve
The safety gas valve is a 24-volt diaphragm valve. It is designed to operate with supply pressures of 4-13 inches w.c. (1.0 to 3.2 kPa). To remove the gas valve, shut off 120-volt power. Shut off the main gas supply to the unit. Disconnect the gas supply piping from the back of the unit. Disconnect the electrical wires from the valve, and unscrew the gas valve from the gas train. Re-assemble in reverse order. A bleed line from the diaphragm type automatic valve shall be vented per local code requirements.
7.2.5Manual Reset High Limit Control
The high limit switch is manual reset switch with an adjustable set point, up to 240°F (116°C) on boiler models and 200°F (93°C) water heater models. To replace the switch, shut off the 120-volt power to the appliance. Remove the cover from the switch to access the mounting screws. Remove the screws, and pull the switch off the control panel. Replace in reverse order.
7.2.6Temperature Control
The temperature control consists of an adjustable electronic control and digital display module. To replace the control or the display, shut off the 120- volt power to the appliance. Remove the cover from the control panel, and remove the screws from the DIN rail clip, to which the controls are mounted. Pull the electrical connector from the controller. Slide the controllers from the DIN rail clip. Replace in reverse order.
7.2.7Auto Reset Temperature Limit
The auto reset temperature limit has a 200°F (93°C) setting. The is mounted directly onto the Brute Magnum header, on the inlet to the copper coil. It senses the inlet water temperature to copper coil, and guards against a malfunctioning mixing system. To replace the switch, shut off the 120-volt power to the appliance. Remove the cover from the switch to access the mounting screws. Remove the screws, and pull the switch off the control panel. Replace in reverse order.
Figure 29. Control Panel.
7.2.8Mixing Control
The FX05 mixing control is the device that
controls the position of the mixing valve system. This control is factory set, and must not be adjusted, except for the °F or °C choice. To remove the control, unplug the wires from the back, push on the tabs to slide the clasping mechanism off, and pull the controller out through the front of the panel. Replace in reverse order.
7.2.9Mixing Valves
There are two 2-way mixing valves that are linked and connected to a valve actuator to create the 3-way mixing system. To remove the upper right valve, remove the actuator and then remove the 2 bolts that connect the sheet metal to the valve. Remove the linkage from the arm that is welded to the actuator. Remove the four bolts on the valve, and slide the valve out. To remove the lower left valve, remove the 2 bolts that connect the sheet metal to the valve. Remove the linkage from the arm that is welded to the actuator. Remove the four bolts on the valve, and slide the valve out. Reassemble in reverse order.
