In this blog, Richard Ryland, National Specification Manager here at Switch2, reflects on the year so far following the launch of our now award-winning ICON HIU, sharing his thoughts on the lessons learned and the progress made.

After a particularly busy year, which included a high of the ICON Connected HIU (Heat Interface Unit) being awarded ‘Physical Technology of the Year – Heating & Cooling’ at the Energy Awards, I have finally found some time to reflect on how the last year has gone.

Reviewing things that I may have to revisit, identifying new focuses, and evaluating lessons learnt, now we have over 2,000 ICON units out in the marketplace. I personally wanted to spend some time re-visiting the CIBSE CP1 2020 and subsequent Design Guide, as although I had studied them in detail at time of launch and refer to them weekly, if not daily; I tend to find I’m always concentrating on specific areas and may have forgotten some of the other key details. One of the elements that was highlighted in doing so, was the performance measuring and testing mentioned in the Design Guide. This section focuses specifically on commissioning, performance verification and recommends that testing is carried out at either annual, or at a minimum, biennial intervals during the operational life of the communal heat network.

What immediately struck me was how far we have come since these documents were written, and how our systems and procedures have already far surpassed this - and for good reason!

If you are only carrying out these verification/performance tests yearly, then the impact on the overall efficiency, the fuel bills and the tariff to the end user could be enormous. Especially in a period where we have seen gas prices rise so dramatically, the impact is being seen and felt in every household. Our experience has shown that doing this on an ongoing basis, allows for the implementation of targeted maintenance programs, which provide effective intervention and lead to real savings across the life of the network, while also providing a more reliable service to the resident.

In a study we carried out using real world data sets, when <10% of the tertiary systems or HIUs were performing badly, they could contribute >80% of the primary system flow rate. This affects both the main system pumping requirements but also adversely affects the return temperatures, increasing heat loss and having a negative impact on the main heat source generator.

An example of methodology using the Automatic Meter Reading (AMR) system to collect flow and energy consumption and how to then calculate the average ∆T over a period, is given in CIBSE CP1 2020 (Page 137). However, we discovered it was easier to just use the first, significant part of the methodology to calculate the volume to energy ratio and then band the properties into three sectors, the good, the bad and the ugly! Simply put it allows:

1.      A quick measure to find poorly performing HIU and or Tertiary Systems.

2.      It’s the amount of primary water needed to deliver 1kWh of Energy.

3.      The less volume of water needed the lower the return temperature will be.

Identifying poor performing properties quickly and efficiently has become a minimum standard within the monthly review on the systems that we operate and maintain. On the sites with the ICON connected HIU, and where we have access to the energy centre/block meters, we can identify if the issue sits within the primary system, the individual HIU or poorly performing tertiary heating, before even attending site. It allows us to target the quick win, non-intrusive interventions, which we have seen reduce return temperatures by up to 15°C and reduce cost of supplying heat by 10%. On sites where we start to take more intrusive interventions savings can go up to 22%.

What I’ve learnt beyond doubt is that continual holistic systems analysis, driving targeted resolutions to specific issues should be the new standard maintenance program. This allows for the maintaining of efficiency year-round, reducing out of hours call outs, and most critically of all, delivers affordable reliable heat to residents.

If you’d like to discuss the benefits and capabilities of our award-winning ICON connected HIU, then feel free to contact me, and I’ll be more than happy to answer any questions on the unit or demonstrate our ICON HIU management portal.