Altecnic launch new compact anti-freeze valve, iStop® PLUS

With a compact design and the ability to install the valves vertically in parallel providing a solution for the most restricted spaces.

Altecnic, the UK’s leading supplier in hydronic solutions and part of the Caleffi Group, has launched the new compact anti-freeze valve, the iStop® PLUS into the UK market.

Setting the standard in efficiency and convenience, the iStop® PLUS boasts a compact size, as well as a sensor on the side, differing to traditional anti-freeze valves, offering remarkably small dimensions without compromising performance.

Key features of the iStop® PLUS include:

  • Compact size.
  • Installation in restricted spaces.
  • Ability to vertically install the valves in parallel.
  • Extreme sensitivity to water temperature.
  • Ability to work with high temperatures.

Its innovative design, featuring an off-axis sensor configuration, enables installation even in the most restricted spaces, catering to the diverse needs of modern installations. Furthermore, the iStop® PLUS has been designed to allow for a pair of valves to be installed vertically in parallel, meaning that installers can seamlessly install valve pairs without the need for minimum spacing. This flexibility not only streamlines installation processes but also optimises space utilisation.

Less space is also required for drainage underneath the valve, making it suitable for connection to self-contained heat pumps with connections for pipes at the bottom of the casing.

Equipped with an exceptional sensitivity to water temperature, the iStop® Plus boasts heightened responsiveness to ensure prompt and precise performance, enhancing system reliability and user confidence. With this, the new anti-freeze valve is engineered to withstand high water temperatures of up to 90 °C. This durability allows the valve to operate with any heat pump and underscores Altecnic’s commitment to delivering products of high quality and performance.

Gary Perry, Managing Director at Altecnic, commented,

“With the iStop® Plus, we are introducing a solution that addresses the evolving needs of modern installations that installers are faced with. Its compact size, coupled with its ability to function in restricted spaces, offers flexibility and ease of use. ”

“At Altecnic, we strive to innovate, quality solutions that meet and exceed the expectations of our customers so that they can remain ahead in our industry as the shift towards Net-Zero solutions continues.”

Find out more about the new iStop® Plus at

Altecnic Ltd is the UK’s leading supplier of hydronic solutions. Established near Stafford in 1987, the company imports and supplies over 5,000 product lines to distributors throughout the UK and Republic of Ireland. The company provides trade merchants, plumbing and heating engineers and specifiers with a comprehensive range of plumbing products, including; thermostatic mixing valves, underfloor heating, sealed systems, dirt and air separation, backflow prevention and vessels and a whole lot more.

Altecnic’s mission statement is to deliver the highest quality products and services to its customers, through manufacturing excellence, innovation and education. Their extensive range of products and services are chosen by trade merchants, original equipment manufacturers, plumbing and heating engineers and specifiers.