King's School Canterbury

The installation of the technically advanced ENiGMA descaling system has resulted in King’s School being able to reduce the use of the boiler in one of its girls boarding houses by a massive 62% in just two months. Now clear of scale, the boiler is able to heat water from 46C to 56C in just two hours forty minutes, compared to six hours twenty minutes preceding the installation of the ENiGMA system – saving 58% in energy costs.

Situated in an urban environment in the historic town of Canterbury, Kent, King’s School was originally established in 597AD, making it Britain’s oldest school. An independent, co-educational day and boarding school, King’s School caters for 769 pupils aged 12 to 18 years.

As Kent is situated in one of Britain’s hardest water areas, with a hardness factor of around 508ppm, the school was badly affected by limescale, which built up in the pipelines and water-fed equipment. This resulted in poor temperature differentials between flow and return at the extremities of the circuit, scale in the bathrooms and kitchen and failure of the boilers to heat water to  the set-point of the secondary thermostat.

When limescale build-up began affecting the water flow at one of the boarding houses, built four years previously, it was decided to install an electromagnetic scale inhibitor. However, when the calorifier was opened for inspection some months later, it was found to be completely full of scale.

Looking for an alternative product that would not only extend the life of capital equipment but also reduce energy costs, the school decided to evaluate the ENiGMA Electronic Descaling System from Environmental Treatment Concepts (ETC).

To monitor performance of the system, ETC installed a data logger, which took temperature readings of the treated water every 15 minutes over a 3-month period. The raw data recorded (see below) clearly shows that, prior to treatment, the boiler remained on constantly during the day because the water was never heated sufficiently to operate the thermostat. However, in just 2 months the heat exchanger efficiency increased because of descaling and the boiler now maintains temperatures correctly. Energy savings are obvious as the boiler now runs for 6.5 hours a day instead of 17.

Commenting on the system, Gavin Merryweather, Domestic Bursar, said: “We are delighted with the ... ENiGMA descaling system and will be gradually installing it throughout the school as funds become available. Being in such a hard water area can result in the early renewal of capital equipment. The system will not only help reduce energy bills but will also increase the life expectancy of items such as boilers, calorifiers and laundry equipment”.

Since the ENiGMA was installed on the calorifier, other units have been successfully fitted at other locations around the school. King’s School is also considering installing on its swimming pools the award winning ENiGMA Olympic unit, which dramatically reduces chemical usage, providing payback in just 18 months. In addition, savings can be achieved from not having to replace valves and bundles in the swimming pool heat exchangers.

Before

After