Install Instructions

4 Hydronic piping

Installation & Service Manual

RELIEF VALVE

Figure 4-1_Relief Valve - CBN315-500

This appliance is supplied with a relief valve(s) sized in

accordance with ASME Boiler and Pressure Ves sel Code,

Section IV (“Heating Boilers”). The re lief valve(s) is mounted

directly into the heat ex chang er inside the header (see

FIG.’s 4-1 and 4-2). To pre vent water damage, the dis charge

from the relief valve shall be piped to a suit able 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.

FLOW SWITCH

Figure 4-2_Water Flow Switch - CBN315-500

A water flow switch is available as a factory sup plied 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 cir cuit to prove water flow before main burner

ig ni tion. A flow switch installed with the fac to ry sup plied

minimum adjustment setting requires a spe cif ic 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 con tacts and

operate the appliance.

Relief Valve

Water Flow Switch (if equipped)