Taking control of energy


“Is my school avoiding energy wastage as much as possible?” It’s a question school children may consider when they cover energy management while studying climate change. And the same question is being asked by head teachers, school governors and local authorities, who have economics in mind. Most schools now look after their own fuel budgets, so every pound saved is of great value.

My company, RG Combustions, has been, for over 30 years, the leading installation and service sub contractor to schools on the Isle of Wight, where we are based. We always aim to provide ‘best value’ to our clients, in the installation itself and its long term energy efficiency and running costs – so have embraced the concept of CentraLine by Honeywell. It allows us to start small and upgrade the system as finances allow. As a CentraLine by Honeywell Partner, we receive valuable training and enjoy technical support by Honeywell specialists whenever necessary.

We were very interested to hear, in Spring of this year, that CentraLine systems for HVAC automation were to be marketed to schools with the dual benefits of cutting heating bills and providing a valuable classroom resource to teach energy efficiency – pupils can access their school’s CentraLine by Honeywell system on any networked PC to see clearly how their indoor environment is being managed to ensure their comfort, while avoiding burning more fuel than necessary. They can see, for example, how the schedule heats rooms being used, avoids overheating and applies optimum start, to the extent that the time the boiler starts each morning varies automatically with the weather.

Looking to the future

Our first CentraLine installations have been with Panther controllers, to replace existing failed controllers. Panther provides easy, local access to all datapoints, status and alarm information, and features a very user-friendly interface using plain language. It employs the LONWORKS communication standard, so is future-proof. We have full flexibility at any time in the future, as other components fail and finances permit, to install further CentraLine components to improve the system.

By comparison, with previous control systems, it was necessary to think: “Will they need this or that on the day?” because, once the choice had been made, there was little flexibility.

Panther installations to date have not been supplemented with the CentraLine PC web-based browser, Arena, but we anticipate schools will invest in these to provide comprehensive HVAC system management locally from the school, or elsewhere via the internet, if they wish.

Arena will allow authorised personnel to prepare a standard schedule of rooms that will be used on each day of the week and the times they will be used. When necessary, they can also override the schedule instantly as needed, such as a single room or rooms for after-school tutorials, the gym for a sports event or even the whole building.

Arena also enables users to view system and environmental data from any PC on the school network or remotely via the web. It opens up the exciting possibility that pupils can monitor the system to study how it works in real time. This practical demonstration will be good for their IT skills and also build an understanding of how control systems work; monitoring variables and the many ways they use this data to minimise energy consumption. The interface is intuitive, so is very easy to use and understand.

The way forward

Our first experience of applying CentraLine by Honeywell in a school was at a High School comprising several buildings served by a district heating system. The original boiler room now serves 80% of the site using three 550 kW boilers. It had a control system, after an optimiser was installed, but this didn’t provide the flexibility needed. When the optimiser failed, the cost of replacing it with another was prohibitive compared with installing a new system – it was decided CentraLine was the way forward. We retained the valves, installed a Panther controller and CentraLine Command room sensors (plus wiring as necessary) all for less than the cost of the original optimiser.

Installation and commissioning were very straightforward. I can programme the Panther in the office, and then simply hand it to a colleague with no controls background to wire it into the panel.

The heating system comprises two constant temperature circuits – one circuit includes radiators and fan convectors. If we were to put a mixing valve on the circuit, as is provided on the other circuit, the radiators would work well but the fan convectors would cut out periodically because they require a certain temperature.

The problem was solved by programming the Panther to think that it has a virtual valve, using a CentraLine Command temperature sensor in the building with an adjustment of +/- 3°C from the set point.

Further energy savings

Budgetary constraints meant it was not possible to provide an Arena workstation at the same time, but we hope this will be approved soon, as the school and Local Authority appreciate how it will enable them to make significant further energy savings by providing in-depth analyses of how the system is performing – accessible locally or remotely – and complete flexibility over where, when and how much heat is delivered to each part of the school. We hope access to the system will eventually be extended to students via the school network and so provide a live demonstration of energy-saving technology.

One of the great confidences we and our clients have in the CentraLine system is that it is designed to be added to and enhanced very easily at any time in the future – unlike previous systems which provided little scope for expansion.

However, the basic system installed already provides much more control over time, temperature and heated location than has ever been available previously. Even in the absence of the detailed scheduling provided by Arena, we have tied down the heating times far more precisely and have, for example, programmed the system to reduce temperatures by one degree C during breaks and the lunch period. This may not sound much, but it contributes to energy savings and allows us to show clients what is possible with a Panther controller and how much more will be achieved by expansion.

We applied a similar approach to initiate CentraLine by Honeywell at a Primary School. This smaller school was heated by two atmospheric cast iron, light commercial boilers which we replaced this year with two new Ideal “Imax Plus” high efficiency condensing boilers. As part of this project we were asked to install a Panther to replace an existing controller, due to its success elsewhere. The Panther provides superior control of the Imax boilers.

Again, the adoption of CentraLine by Honeywell will allow easy system expansion and replacement and upgrading of components at any time in the future.

The best way forward

As a sub contractor working on installations such as schools, public and civic buildings and others that must improve through evolution due to budgetary constraints, we are confidant that CentraLine by Honeywell provides the best way forward for HVAC automation. The system can be developed over many years, both as existing system components become due for replacement and as funds are made available for additional energy-saving enhancements, which is excellent news for anyone in a budget challenged position!

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