Raypak 850, 300 operating instructions Wiring the Outdoor Sensor, Wiring the Indirect Sensor

Wiring the Outdoor Sensor

1.There is no connection required if an outdoor sen- sor is not used in this installation.

2.If using an Outdoor Sensor, connect the wires for sensor to the terminals marked OUTDOOR SEN (shown in Fig. 16) in the electrical junction box. Caution should be used to ensure neither of these terminals becomes connected to ground.

3.Use a minimum 22 AWG wire for runs of 100 feet or less, and minimum 18 AWG wire for runs of up to 150 feet.

4.Mount the outdoor sensor on an exterior surface of the building, preferably on the north side in an area that will not be affected by direct sunlight and that will be exposed to varying weather conditions.

Wiring the Indirect Sensor

1.There is no indirect sensor connection required if an indirect water heater is not used in the installa- tion.

2.The XFyre boiler will operate an indirect fired water heater with either a thermostat type aquas- tat installed in the indirect tank or a Raypak tank sensor. When a tank sensor is used, the XFyre control will automatically detect its presence and a demand for heat from the indirect water heater will be generated when the tank temperature falls below the user settable setpoint by more than the user selectable offset. The demand will continue until the sensor measures that the indirect water heater temperature is above the setpoint.

3.Connect the indirect tank sensor to the terminals marked DHW SENSOR (shown in Fig. 16) in the electrical junction box. Caution should be used to ensure neither of these terminals becomes con- nected to ground.

Wiring the Optional 0–10 Volt Building Control Signal

1.A signal from a building management system may be connected to the XFyre boiler to enable remote control. This signal should be a 0–10 volt positive DC signal. When this input is enabled using the installer menu, a building control system can be used to control either the setpoint temperature or the heat output of the XFyre boiler. The control interprets the 0–10 volt signal as follows. When the signal is between 0 and 1 volt, the XFyre boiler will be in stand by mode, not firing. When the signal rises above 1 volt, the XFyre boiler will ignite. As the signal continues to rise towards its maximum of 10 volts, the XFyre boiler will increase either in setpoint temperature or firing rate, depending on the setting of screen 17 in the installer menu. See the Installer Menu section for details on the setting of screens 16 and 17 for this option.

2.Connect a building management system or other auxiliary control signal to the terminals marked +0–10 V and -0–10 V in the electrical junction box (shown in Fig. 16) Caution should be used to ensure that the +0–10 V connection does not become connected to ground.

Wiring the Cascade System Communication Bus

1.Use standard CAT3 or CAT5 computer network patch cables to connect the communication bus between each of the boilers. These cables are readily available at any office supply, computer, electronic, department or discount home supply store in varying lengths.

2.It is recommended that the shortest length cable possible be used to reach between the boilers and create a neat installation. Do not run unprotected cables across the floor or where they will become wet or damaged. Avoid running communication cables parallel with, or close to or against, high voltage (120 volt or greater) wiring. Raypak rec- ommends that the total maximum length of communication bus cables not exceed 200 feet.

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