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The hotun product development story

hotun has been developed by RA Tech UK Ltd a company founded by experienced and respected plumber Russell Armstrong and this is the?hotun product development story

Russell’s long experience in the building industry has led him to understand the practical problems that installers and trades people face when driven by the demands of certain regulations. The introduction of new products to meet those regulations is a challenge in itself and to devise a simple and effective way to solve a problem is what Russell set out to do.

Having come up with the idea of hotun, he formed his company, with fellow director (and wife) Ally Armstrong, RA Tech UK Ltd. He has invested in patenting the product, testing it fully, and getting it approved by relevant industry bodies. A major investment in tooling and commissioning all manufacturing to ISO9000 local companies, means that hotun can be specified and installed with confidence, and is offered with a 5 year warranty.

The story

Via his (then) plumbing company (Integrated Interiors Plumbing and Repairs), Russell was commissioned to carry out a tea point installation in a landlocked interior office space at a locally (Derby) based company Johnsons removals.

Johnsons MoversHaving no access to a drain he needed to install a macerator to pump the water away. He also installed a local 15l unvented hot water cylinder underneath the sink. To comply with the regulations he knew that there had to be a visible means of discharge (via a standard tundish) but how would the smells be dealt with? Hard piping was out of the question (although he had seen that done in many installations) because it contravened the regulations on various counts. So in this instance he had to fit a second fully enclosed self sealing valve (see picture left). Two products did the job but why wasn?t there something else out there that would resolve the issue as a one product solution?

Despite scouring the market and with the help of his local merchants, Willbond (Derby) they could find no viable alternative.

This made Russell think about an alternative solution, So he sat down and began to develop his ideas, and with the aid of 3D printing technology produced his first prototype (see pictures). Every component in hotun is bespoke design. He has used British based companies to work with to help develop the product, from a spring and diaphragm to the bolt assembly, all uniquely designed specifically for the product.

Russell can proudly claim that the product is entirely manufactured in the UK and many parts produced locally, and assembled in his home region of Derbyshire.

From the 3D prototype he commissioned a company to produce the professional graphic drawing package that would enable the injection molding tooling to be made. Further tests were carried out at various points of the design process, the spring was refined both in terms of production tolerance but in ease of manufacture. With environmental concerns about single use transportation packaging, Russell and the Spring manufacturer (Advanex, Nottingham) developed a reusable blister tray system for the springs. This is not only reusable but it also had the added manufacturing benefit of ensuring that the delicate springs did not become entangled. Although at a slight cost penalty to initially package to transport to the assembly plant, the overall cost benefits (at assembly stage), re-use of the trays environmentally outweighed the dissadvantages.

The high quality, high grade EPDM sealing diaphragm (Made by SRM Ltd, a Hatton,Derbyshire based rubber company) was carefully tested to ensure that an air tight seal was created to stop the odours coming back up. The shoulder bolt went through several alterations to ensure repeatability of the trigger point of the device. Hundreds of tests were carried out to determine the optimal balance between trigger point and an effective seal. It has been no easy task to undertake but Russell has stuck to his vision and is now ready to take the product to market.

To find out more about Russell please view his LinkedIn profile (social media icon in the header)

(Picture) #hotun product development transition from 1st 3D printed prototype to production product


Since developing the hotun product, Russell has spent more and more time away from his actual plumbing business, to the extent that he is now working full time at RA Tech. His plumbing business has taken such a back seat that it no longer makes sense to keep the company running and as such he has closed that business.