Arizona boilers from Automatic Heating have been installed at several leading Australian hospitals to achieve redundancy in critical heating processes.

The ongoing operation of healthcare facilities depends on the uninterrupted operation of critical heating processes. Dual fuel burners can help these facilities achieve redundancy in their heating systems, ensuring continued operation in the event of a disruption in primary fuel supply.

While most boiler plants will have a backup system of some kind, a backup boiler that relies on the same fuel won’t provide any level of redundancy. Therefore, boilers that can operate on dual fuels provide the ultimate in redundancy.

Boilers typically use one of three fuels – natural gas, LPG or light oil – depending on their location. In Australia’s capital cities, natural gas is the preferred fuel for boilers due to its clean burning, lower greenhouse gas emissions and continuous supply. The use of a dual fuel boiler that can utilise the constant supply of natural gas in normal operation, and switch to a secondary fuel source such as diesel or LPG in the event of a natural gas supply failure, will ensure a high level of redundancy.

In areas where natural gas is not supplied, a dual fuel boiler that can operate on LPG as a primary fuel, but also operate on a secondary fuel such as light oil (diesel) not only provides redundancy in the event of a fuel disruption, but also offers the advantage of being able to use the cheapest fuel at any given time.

Arizona boilers

Automatic Heating’s Arizona boilers have been designed to operate efficiently on dual fuels when combined with the Enterprise dual fuel power burner that can operate using natural gas, LPG or light oil. The burner features automatic fuel changeover and an onboard electronic combustion manager.

The Arizona boiler is a high output boiler made entirely of carbon steel. A scotch marine boiler, it features three combustion gas passes, with the wet back of the cylindrical combustion chamber improving heat exchange between the combustion gases and the water. The combustion gas passes through the tubes at very high speed and turbulence, which is accentuated by specially designed turbofans that also help with heat exchange.

This combination provides modulation of 1:5, and a gross efficiency of 85-87 per cent. An add-on economiser allows even greater efficiencies to be achieved.

Available in 150kW to 5000kW models, the Arizona range offers the option of cascading the boilers together to meet larger capacity requirements.

Automatic Heating’s Arizona boilers have been installed in a number of high profile projects where dual fuel is providing redundancy to critical processes. These include the new Royal Adelaide Hospital where six 3000kW Arizona boilers are operating across two identical plant rooms (for redundancy) on natural gas, with light oil used as the secondary fuel source for redundancy.

The Launceston General Hospital uses an Arizona boiler set that operates on natural gas, with LPG used as a secondary standby fuel.

Arizona dual fuel boilers have also been installed at the recently completed Victorian Comprehensive Cancer Centre, as well as the under construction Perth Children’s Hospital and Monash Children’s Hospital.