Patterson-Kelley MOD-04 Boiler Inlet and Outlet Connections, Boiler Water Piping by Installer

Modu-Fire®Gas-Fired Boiler

Consideration must be given to all possible condi- tions and their consequences.

Piping With Refrigeration Machines

When used with a refrigeration system, the boiler shall be installed so that chilled medium is piped in parallel with the boiler. Valves should be installed to prevent chilled water from entering the boiler when the system is operated in the cooling mode.

Piping With Air Handling Units

The boiler piping system of a hot water heating boiler connected to heating coils located in air han- dling units, where they may be exposed to refriger- ated air circulation, must be equipped with flow control valves or other automatic means to prevent gravity circulation of the boiler water during the cooling cycle.

3.8.2 Boiler Inlet and Outlet Connections

Relief Valve
Drain
	Union
	Outlet (to
	system)
	Isolating
	Valve
Isolating
Valve
	Inlet (from
Boiler	system)
Drain
Strainer	Isolating
	Valve
Boiler Inlet and Outlet Connections

Make water connections as the application warrants, or at a minimum, as shown, but always in compli- ance with the local requirements.

Installation

Note: Pipe unions and isolating valves must be installed in both water connections for ease of service.

The bottom connection to the boiler is the INLET and must be used for the return from the system.

The top connection to the boiler is the OUTLET and must be connected as the supply to the system.

Piping must be installed such that no piping stresses are transmitted to the boiler. The boiler should not be used as a pipe anchor.

3.8.3 Boiler Water Piping by Installer

Strainer

To avoid possible contamination of the boiler with dirt, rust or sediment from the system, a strainer near the boiler inlet is strongly recommended. Even new systems may contain sufficient foreign material to eventually reduce the performance of the heat exchanger. Adequate circulation of good clean wa- ter is essential to maximum efficiency and long life of the boiler.

Relief Valve and Piping

Each boiler is supplied with a pressure-relief valve sized in accordance with ASME requirements. The relief valve should be piped to a suitable floor drain. Reducing couplings or other restrictions are not permitted in the discharge line.

Low Water Cut-off

The boiler is furnished with a flow-switch-type low water cut-off as required by Section IV ASME Code; no field piping is required. If the flow switch does not sense water flow, the boiler will shut down and a red indicator will be illuminated on the control panel. This flow switch only proves that flow is present. It does not prove adequate flow as required by this boiler.

Installation of an external low water cutoff or man- ual reset low-water switch may be required by cer- tain codes or in certain installations. Consult your local code for details.

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