Boilers / Instant Water Heaters


Immergas was founded in 1964 for the design and manufacture of gas boilers for domestic use. Over 55 years of experience and more than 7 million boilers installed make Immergas one of the leading companies in the heating sector in Italy and in several European countries.
Greater attention to alternative energy and gas consumption savings have given Immergas a leading position in the production of innovative technologies. Through its new Research Centre the company is investing further in the design of evolved hybrid systems, and producing electronically-controlled systems that can select the more cost-effective energy source from among condensing boiler, heat pump, solar panels and photovoltaic system, in order to generate heat or cool air with the least amount of energy consumption.
This is why it is one of our main boiler brands at NAS Limted. Quality in products and services, equally.
Our team of experts as NAS Limited have great knowledge and expertise with years of experience working with the brands. With high-level training on the latest standards and technologies in the field together with the quality of products make Immergas and NAS your best solution for water boilers. Oure technicians thus have the best possible knowledge of products and systems, are up-to-date with the most recent solutions and ensure high standards of maintenance.


Unical is a leader in the heating systems, solar industry. It boasts an extensive product catalogue which is split into three macro-categories: domestic, professional and industrial. This breakdown allows a rapid identification of the most suitable solution for all types of requirements, whether a family, i.e. domestic usage, or professional or industrial.
For Unical, technological research in the spheres of heating systems, solar and systems and air conditioning systems is a fundamental aspect. Technology means having systems and plants that guarantee the best performance levels, maximum safety and total environmental friendliness.

Unical products guarantee maximum efficiency and superior quality standards for the heating and of your home, of your building or for larger facilities such as industries, hospitals, shopping centres, theatres and other gathering places.

All our services are done using proper boiler equipment such as flue gas analysers to further optimize our services.


Bentone burners are well known for its reliability, efficiency and performance.
Quality, Environment, Reliability and of course Safety has always been the key elements for Bentone.
Low emissions, standards and regulations are our keystones.
The product development team at Bentone always focuses on quality to ensure that they always have a reliable burner before we introduce it to the market!

At NAS Ltd we are proud suppliers and installers of Bentone.