Crown Boiler PHNTM080 - Page 76

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10) Drain Valve (required) – Install the drain valve supplied as shown in Figure 9.9.
11) Low Water Cut-off (may be required by local jurisdiction) – Protection of this boiler against low water and/or
  inadequateowisprovidedbytheUL353certiedowswitchbuiltintotheboiler.Thisisawatertubeboilerand
  thisowswitchisthereforetheonlyeffectivewaytoprovidesuchprotection.SectionHG614(c)ofthe2013 
  ASMEboilerandPressureVesselCoderecognizestheuseofalistedowswitchinlieuofalowwatercut-offon
water tube boilers.
In the event that a local jurisdiction insists upon the installation of a low water cut-off with this boiler, a low water
cut-off kit is available that plugs into the low voltage circuit board (see Part X). Install the low water cut-off in the
supply piping at the point prescribed the local jurisdiction (generally at a point above the boiler).
If a probe type low water cut-off is used, be certain that it is located at a point in the piping from which air can escape to an
automatic air vent. Generally, this means that there should be no down-turns in the piping between the low water cut-off and
the point where the automatic air vent is installed. Failure to do this may result in nuisance boiler shut-downs due to small
amounts of air trapped around the probe.
FIGURE 9.9: FACTORY SUPPLIED PIPING AND TRIM INSTALLATION