Therefore , most continental standards are based on minimising the oxygen entry and using water with a conductivity below 100 µ S / cm ( VDI2035 Part1 ). In some parts of the UK mains water would meet these requirements without any further conditioning . The low conductivity slows down corrosion and microbiological processes . Any corrosion that may occur would not be damaging and can easily be monitored .
A non-chemical approach is not only better for our environment but also offers more sustainable results and a lower overall cost The CIBSE Heat Networks Code of Practice in the UK ( CP1 ) should be commended in its adoption of alternative approaches such as VDI 2035Part1 .
CASE STUDY
The heat network at Harvesters Way in Edinburgh used the approach in CIBSE document CP1 . It consists of 183 maisonettes , flats and town houses with HIUs and no hydraulic break . By using a central boiler plant of only 400kW the efficiency of the system in comparison to decentralised boilers is around 15 % better .
The inclusion of a Risycor electronic corrosion coupon monitor allows systematic performance monitoring and to provide data for the evidence pack at hand over . The Risycor electronic corrosion monitor alarmed twice in 3 years when maintenance on system was being carried out .
The corrosion data recorded by the monitor shows otherwise vey low levels of corrosion meaning the system runs efficiently and reliably .
CONCLUSION
The case identifies the benefits of adopting a considered design approach to water conditioning opposed to water treatment combined with performance monitoring where quality & quantity of incoming water , enhanced design of system pressurisation and commissioning offers substantial economic justification in terms of ROI .
“ Corrosion tends to be the greatest mystery and astonishment of both stakeholders and FM contractors , who historically just rely on inhibitor levels as their standard bearer whether a system is going to be okay . An online corrosion monitor such as Risycor provides transparent real time and proactive assistance to the process to allow better financial , educated and long term planning for any system .” James Culbertson of The Keenan Consultancy
Figure 1 Continual performance monitoring and use of the evidence pack has arrived in CP1
Post Practical Completion introduction of Electronic Coupon Corrosion Monitoring initial 6 weeks forming evidence of a stable system in the handover pack
This new technology has been widely used in other systems for a few years now , particularly where clients and manufacturers have sought greater transparency on system performance at commissioning and beyond . The benefits of the monitoring technology can be applied in all such systems regardless if the water comes straight from the tap , has been conditioned or chemically inhibited with minimal capital expenditure .