User Guide

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 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2015 
  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, refer to Part X
  andthelow-watercut-offmanufacturer’sinstructionsforproperwiring.Installthelowwatercut-offinthesupply
piping at the point prescribed by 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 9.6: FACTORY SUPPLIED PIPING AND TRIM INSTALLATION
D. Piping for Special Situations
1) Systems containing oxygen - Many hydronic systems contain enough dissolved oxygen to cause severe corrosion
damage to a this boiler. Some examples include:
   •Radiantsystemsthatemploytubingwithoutanoxygenbarrier.
   •Systemswithroutineadditionsoffreshwater.
   •Systemswhichareopentotheatmosphere.
If the boiler is to be used in such a system, it must be separated from the oxygenated water being heated with a plate heat
exchanger.Consulttheheatexchangermanufacturerforproperheatexchangersizingaswellasowandtemperature
requirements. All components on the oxygenated side of the heat exchanger, such as the pump and expansion tank, must be
designed for use in oxygenated water.
2) Piping with a Chiller - If the boiler is used in conjunction with a chiller, pipe the boiler and chiller in parallel. Use
isolation valves to prevent chilled water from entering the boiler.
3) Air Handlers-Wheretheboilerisconnectedtoairhandlersthroughwhichrefrigeratedairpasses,useowcontrol 
valves in the boiler piping or other automatic means to prevent gravity circulation during the cooling cycle.