Lochinvar 500, 90 service manual Hydronic piping, Relief Valve, Water Flow Switch if equipped

Installation & Service Manual

4Hydronic piping

Relief Valve

RELIEF VALVE

Figure 4-1_Relief Valve - CBN315-500

Water Flow Switch (if equipped)

FLOW SWITCH

Figure 4-2_Water Flow Switch - CBN315-500

This appliance is supplied with a relief valve(s) sized in accordance with ASME Boiler and Pressure Vessel Code, Section IV (“Heating Boilers”). The relief valve(s) is mounted directly into the heat exchanger inside the header (see FIG.’s 4-1 and 4-2). To prevent water damage, the discharge from the relief valve shall be piped to a suitable floor drain for disposal when relief occurs. No reducing couplings or other restrictions shall be installed in the discharge line. The discharge line shall allow complete drainage of the valve and line. Relief valves should be manually operated at least once a year.

￿ CAUTION Avoid contact with hot discharge water.

A water flow switch is available as a factory supplied option on all heating boilers and water heaters (see section 7). The flow switch should be wired between terminals X and B. Remove the jumper between the X and B terminals on the terminal strip. This wiring connection installs the flow switch in the 24 VAC safety circuit to prove water flow before main burner ignition. A flow switch installed with the factory supplied minimum adjustment setting requires a specific minimum flow to make the switch and start burner operation. The flow rate required is a function of the diameter of pipe and tee used for installation. Ensure that the pump installed on the boiler will supply adequate flow to make the flow switch contacts and operate the appliance.

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