R020932J1, Install Manual

SECTION IV - FUEL SYSTEM

4.1 GENERAL Clayton’s SigmaFire steam generators are designed to fire on natural gas, propane, or No. 2 distil- late light fuel oil. On combination natural/propane gas and fuel oil machines, each fuel type requires its designated burner manifold to operate. These burner manifolds must be exchanged, manually, to match the fuel-type desired. Characteristics of, and installation guidelines for, both gas and oil fuel systems are described in detail in the following paragraphs. The SigmaFire models SF-25 and SF-35 steam generators/fluid heaters are step-fired combustion machines only. The SigmaFire models SF-50 through SF-200 steam generators/fluid heaters are step- fired as standard, but ordered as modulating on gas combustion and step-fired on oil combustion.

NOTE The installing contractors are responsible for ensuring that all piping and fit- tings are rated for the intended system installation (material type, thickness, pressure, temperature). The installing contractors are also responsible for en- suring the steam system design meets the flow and pressure requirements of a Clayton steam generator (see Section VI, Table 1).

4.2 NATURAL GAS Clayton’s SigmaFire steam generators are built in accordance with ANSI /ASME CSD-1, (C)UL [(Canada) Underwriters Laboratories], FM (Factory Mutual) guidelines, and IRI (Industrial Risk Insurers) /GEGAP compliance. High and low gas pressure switches (with manual reset) are standard on all gas trains. Unless otherwise stated (liquid petroleum and other gas operation requires engineering evalua- tion), the standard Clayton gas burner is designed for operation using pipeline-quality natural gas. Gas supply connection sizes and rated gas flows for each model are provided in Tables 1and 2 of Section VI. The gas supply line must be sized to provide both the supply pressure and full rated flow indicated in Table 1 of Section VI without “sagging” (pressure drop). The gas supply pressure must not vary more than +5% of Clayton’s required supply pressure.

NOTE All gas supply piping must include a minimum 12-inch drip leg immediately before Clayton’s gas train connection, and be fully self-supporting.

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04/22/2015

Sect04_FuelSys_SF_f.fm