Gas valve unit

The gas valve unit (GVU) controls the gas feed pressure according to the engine load. In addition, the unit ensures safe maintenance on the engine and performs a leakage test of the automatic shut-off valves before the engine starts operating on gas. In case of hazardous events, the unit will automatically inert the gas line with nitrogen. A gas valve unit is installed in the fuel gas system for each engine, to control the engine-specific gas pressure.

    Technical data

    Main Components*

    • Manual shut off valve
    • Gas filter
    • Block and bleed valve arrangement
    • Flowmeter (optional)
    • Pressure control valve
    • Nitrogen inerting valves
    • Ventilation valves

    * Available as enclosed type (GVU-ED™️)and Open Type (GVU-OD™️)
    (Include two pictures uploaded below)


    Wärtsilä can deliver the GVU for Wärtsilä 4S engines and 2S WinGD engines for any applicable type of ship

    Technical features

    Wärtsilä Gas Valve Unit enables

    • Efficient space utilisation
    • Minimised amount of interface
    • Unequalled reliability
    • Common Control system with the engines through Wärtsilä UNIC
    Methane number

    Wärtsilä Methane Number Calculator

    We have developed this tool for ship owners and operators to calculate the Methane Number of the fuel gas.
    The calculation result indicates whether or not the given gas quality is suitable for use in Wärtsilä dual-fuel engines.

    Methane CH4
    Iso-butane (2-Methylpropane)i-C4H10
    Iso-pentane (2-Methylbutane)i-C5H12
    Neo-pentane (2,2-Dimethylpropane) neo-C5H12
    Mix-hexaneMix C6H14
    Mix-heptaneMix C7H16
    Carbondioxide C02
    Nitrogen N2
    Hydrogen sulfideH2S
    Total mol%
    Wärtsilä Methane number (WMN)
    Propane Knock Index (PKI)
    The calculation tool is owned by Wärtsilä and is made for customer use and is for guidance only. Changes in the tool is reserved at any time.
    GVU-OD Dimensions
    GVU-ED Dimensions
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    Video - Wärtsilä new and compact LNGPac


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    Related products


    The Wärtsilä Gas Valve Unit Enclosed Design (GVU-ED™) for marine applications

    Wärtsilä’s dual-fuel engine technology is...
    17 May 2013
    • In Detail article

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    Contact us

    Please fill in the form, we aim to respond within 1-2 business days depending on the enquiry. For an existing installation, provide all necessary details to identify the installation and the equipment. Fields indicated with an asterisk (*) are required. 

    Contact our 24/7 customer support at +47 815 48 500. For spare parts, please e-mail us with the equipment serial number or the name of the installation at (Inert Gas Systems) (all other products) 
    For technical support & service, please email us with the equipment serial number or the name of the installation at
    Equipment serial number is taken from the equipment nameplate and includes all letters and numbers as given on the equipment nameplate.

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