QM Packaged Propane-Air Back-Up System

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Packaged Synthetic Natural Gas (SNG) Systems

QM Packaged Propane-Air Back-Up System

The Algas-SDI QM natural gas replacement system is a combination gas fired waterbath LPG vaporizer and atmospheric venturi LPG/air mixer. All QM models feature an Eclipse Combustion ThermAir forced draft burner and Algas-SDI optimized venturi mixers. Operation of these units has been proven in -40 F climates. PLC controls with an easy to use operator interface are provided in a temperature controlled enclosure to ensure long-term reliable operation.

A “Smart-Start” cold start feature automatically senses and controls the inlet propane pressure to make sure only vapor is fed to the burner until the bath is warm enough for full vaporization. When the bath has reached operating temperature an output is switched by the PLC that turns on the LPG pump (STABILAIRE). A maintenance program tracks the hours used, venturi cycles, and burner cycles to allow the user to schedule service accordingly. Flow totalization is also provided for convenience.

QM Packaged Propane-Air Back-Up System

Compact system comprised of vertical waterbath vaporizer and atmospheric venturi mixer


A forced draft burner keeps the waterbath at optimum vaporizing temperature


Powder coated galvanized steel cabinet


Easy to use Operator Interface with PLC and smart controls


Integral heavy ends trap keeps the “gunk” out of the venturi controls


Heavy duty water pump provides circulation and prevents temperature stratification


Systems 100 million and larger use a single pilot operated venturi regulator for robust, consistent control and easy adjustment


Delivery pressures up to 15 PSIG available with commercial propane feedstock, up to 8 PSIG with butane rich LPG, and up to 40 PSIG with compressed air


FM Approved



  • 28 – 150 MMBTU/hr

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Additional Synthetic Natural Gas (SNG) Products

Much like a generator for electricity back-up, ASDI’s packaged (propane-air) systems provide a complete solution for backing up natural gas. We offer a complete range of natural gas replacement systems for industrial and municipal applications as well as gas-air mixers, pumps, and accessories.

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OUR AIM: The innovative application of reliable clean-energy systems for commercial, industrial and utility customers.

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