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GB300 BOILER INSTALLATION AND OPERATION INSTRUCTIONS
Table 4 | Supply & Return Pipe Sizing | |
Boiler Model | Supply Size (in) | Return Size (in) |
5 - 10 section | 3" | 3" |
11 - 21 section | 4" | 3" |
Install the Pressure Relief Valve in the 1 1/2 NPT opening in the top of the end section opposite the gas controls. Pipe the discharge of the Pressure Relief Valve to prevent scalding in the event of a discharge, see Figure 93. The discharge piping must be sized the same as the Pressure Relief Valve outlet.
CAUTION: If the relief valve must be installed on the same end as the gas controls, provisions to protect the controls from water in the event of a discharge must be made.
Locate the Theraltemeter, Low Water Cutoff Device, Hi Limit Control and Operating Control per Figures 94 & 95. Optional controls must be installed in accordance with the control manufacturers instructions and Figure 94.
Figure 95 | Single Water Boiler Piping |
ASME
Safety
Valve
Hi Limit
Control
Temperature
Pressure Gage 
Operating
Control
Piping For Use With Cooling Units
The boiler, when used in connection with a refrigeration system, must be installed so the chilled medium is piped in parallel with the boiler. Appropriate valves must be used to prevent the chilled water from entering the boiler.
When a boiler is connected to a heating coil that may be exposed to refrigerated air from an air handling device, the piping system must be equipped with flow- control valves or some other automatic means of preventing gravity circulation of the boiler water during the cooling cycle.
Steam Boiler Piping Connections
Table 3, contains the steam riser location schedule. Riser, equalizer and header pipe sizes are located in Table 5. A typical single boiler piping arrangement is shown in Figure 95. Figures 97 & 97A contain typical piping diagrams for steam boilers in battery. The steam piping should be pitched so the condensate flows in the direction of steam travel.
