Water heating by electricity.
First we like to point out that it is our opinion that solar-panels on a south facing roof is a more ecological, and in the long run, more economical way of heating the tap-water in a house. However, it is cheaper to install an electrical water-heater initially. If electric water-heating is installed, the house should at least be prepared for future solar heating arrangements by leaving space for a storage tank in the utility room.
The heating of tap-water accounts for a large percentage of a household's energy consumption. A pressurised water system is the most efficient with no need for "power showers", provided that the hot water-tank is highly insulated. Effective insulating lagging on all pipes helps to minimise energy wastage.as well. It is basically a very simple system with a minimal amount of components and potential problems. Direct pressure from a mains supply, or your own pump, feeds the house. After the internal stopcock it is divided into two branches. One branch feeds all the cold water points through a manifold. The other branch goes into the hot water heater and from there to the hot water points through a manifold.
Hot water heater-tank.
Usually referred to as the immersion heater tank. It is constructed to withstand the direct pressure.( Ordinary copper cylinders cannot do this). The tank is made of steel with a porcelain coating that repels bacteria and calcification. The water does not come in contact with copper in the tank - a clear health advantage. Another important detail is the quality of the thermostat - the temperature is infinitely adjustable in the range 5°C to 65°C. The heat losses are minimal because of superior insulation and therefore the heater can be left switched on at all times. Alternatively, night-rate electricity can be used with a time-switch installed; the small heat-losses mean that the water will stay hot from morning to evening. The heatlosses from the unit are exceedingly small so a traditional hotpress arrangement cannot be used as the surrounding cupboard will not get heated. The electric heating element is built into a ceramic-covered tube in the tank. Therefore the water does not come in direct contact with the heater. This precludes lime build-up on the heating-element. It is dismountable for inspection. The unit's clean-cut design resembles a refrigerator and it does not have to be built-in. They are available in many sizes: 35, 60, 110 or 160 litres. The effect of the heating element varies between 1000 - 1500Watt at single phase 230V. They are pressure tested to 13.5bar.
Plumbing and mixers in a water-saving pressurised system.
All plumbing is concentrated to the laundry room. This room, as well as bath and shower rooms are waterproofed and equipped with a floor-trap. The water-supply pipe enters the house here, the water-heater is located here, and all water-pipes originate here. Manifolds divide the hot and cold water supply to cross-link polyethylene pipes that run without interruptions or hidden connectors, directly from the manifold to each tap. This makes the system leak-proof. All hot and cold water pipes are thermally insulated.
The greatest advantage of a high pressure system lies in the saving of water used in each mixer. There is an air injection in the nozzle of the taps which gives the user the feeling of a powerful water-flow. In fact, less water is used in these taps than in ordinary taps. The mixer-taps are one-hand operated. You get the desired temperature almost immediately. The shower mixer is noticeably more comfortable and economical to use in a pressurised system. The kitchen mixer has a built-in safety valve for dishwasher connection. All mixers (except shower) have a ceramic-disc seal which is maintenance free and does not need replacement.