HWAT Revival Special focus on hospitals Hygiene Flexibility Economy

Requirements for Hot Water Systems in hospitals Hygiene & Comfort Flexibility Economy

Available systems for Hot Water Distribution The conventional, expensive solution: the Recirculation System 2. The intelligent, economic alternative: the Hot Water Temperature Maintenance System

Mode of operation of Raychem’s Hot Water Temperature Maintenance system Insulation The water heater heats the water! The heating cable compensates for the heat losses and supplies heat where it is needed. Self-regulating heating cable

35 Years of Experience and competence The self-regulating heating cable was invented by Raychem in 1976 Installed in over 300,000 buildings Over 1000 km of temperature maintenance cable are installed each year Some famous examples: Heathrow, Charles de Gaulle Airport Eiffel Tower Royal Opera House London Numerous hospitals

Requirements for Hot Water Systems in hospitals Hygiene & Comfort Flexibility Economy

Comfort Hot water at tap No maintenance and servicing The demands made on hot water supply systems concentrate, on the one hand, on the comfort of the user (patient), in other words having immediate hot water at the tap ... ….and, on the other hand, on the convenience to the operator (hospital) by avoiding time-consuming and expensive maintenance and servicing of the system (fewer pipes, control valves and pumps). Hot water at tap No maintenance and servicing

Hygiene – legionella in the Hot Water Distribution System Legionella bacteria propagate at: Low flow rates, in oversized pipes Hot water temperatures below 60°C Corrosion and contamination, biofilm Legionella may remain trapped in the biofilm and may therefore resist temperature shock or even treatment with disinfectant.

Hygiene: DVGW requirements for the construction of a hygienic Hot Water Distribution System 5.1 Drinking water heating systems must be designed as small as possible. Recirculation System with return pipe Hot water Temperature Maintenance System The hot water temperature maintenance system has fewer pipes, less water volume, less heat loss and therefore presents a lower risk of bacterial problems.

DVGW requirement 5.2 Drinking water heater The cold water inlet ... must be designed to avoid .. a large mixing zone h Recirculation Recirculation System with return pipe Hot Water Temperature Maintenance System The water heater volume is used efficiently with the hot water temperature maintenance system because there is no drinking water return pipe The zone between cold and hot is not affected

Advantages of the hot water temperature maintenance system in terms of hygiene: legionella prevention Shortest pipe network of all central hot water systems (“half pipe length”) Guaranteed high temperature throughout the system over the entire length No unheated zones Temperature maintenance Possible as far as tap point Temperature increase of up to 70°C possible Efficient use of the water heater No return pipe Renewal of water in the pipe network Pipe volume is 100% renewed with each tapping process because water flows in one direction only

The hot water temperature maintenance system provides comfort and a hygienic hot water supply Shortest drinking water heating system Most efficient use of drinking water heater Guaranteed high temperature throughout the system over the entire length Legionella prevention Hygiene & Comfort

Requirements for hot water systems in hospitals Hygiene & Comfort Flexibility Economy

Space-saving and flexible: Simple installation for an extension or new building One pipe (including insulation) less High degree of flexibility when making modifications to the pipe network: Adaptations regardless of hydraulic alignment! Construction, during renovation work, can be split in sections (time factor) without influence on complete hot water network Self-regulating heating cable can be easily shortened or lengthened, in the case of an extension

Flexibility: Leasing to third parties Because of cost pressure there is an increasing trend towards leasing consulting rooms to established specialists or specialist institutions Simple measurement of the hot water consumption is possible by means of conventional water meters at any point with the hot water temperature maintenance system This in turn allows leasing by station or room because of accurate, separate cost invoicing.

Flexibility: Complementary to the recirculation system Hot Water Temperature Maintenance system can be complementary to the recirculation system, where this is sensible Heating cable

The Hot Water Temperature Maintenance System offers enormous flexibility! For extensions In case of modifications Space saving For subletting Flexibility

Requirements for hot water systems in hospitals Hygiene & Comfort Flexibility Economy

Savewatt economy comparison between recirculation and Hot Water Temperature Maintenance Comparison on the basis of a real calculation in a hospital equipped with recirculation

Savewatt calculation- Model Hospital East Wing Basic data Recirculation Stainless steel pipes Supply: 363 m Return: 354 m Mineral wool shell insulation (thickness according to german standards) Fittings: Circulation pump 1 off Pump shutoff valves 2 off Line control valves 12 off Shutoff valves 12 off Temperature maintenance system Stainless steel pipes Supply: 363 m Mineral wool shell insulation (thickness according to german standards) 4 heating circuits HWAT-R 375 m Switch cabinet SBS-06-HV-ECO-10 RayClic-CE-02 4 off RayClic-T-02 12 off Fastening materials Stammdaten not yet updated with recent costs: Rohre, etc

Savewatt calculation – Model Hospital East Wing Basic data Energy prices: Natural gas: 0.044 Euro/kWh Electricity: 0.15 Euro/kWh Thermal parameters Water heater temperature Output: 60°C Input: 55°C Maintenance temperature of Hot Water Maintenance System: 55°C Ambient temperature: 18 – 22 °C Efficiency rating Recirculation: 72% Efficiency rating of water heater: 90% Yearly efficiency rating of total warm water system: 80% Temperature Maintenance System: 76% Efficiency rating of water heater : 95% Yearly efficiency rating of total warm water system : 80%

Operating costs: only 36% energy demand and 10% lower operating costs Energy efficiency ratings (boiler x total warm water supply) Recirculation: 72 % Hot water temperature maintenance system: 76 %

Depreciation 10% yearly saving on capital and operating costs Basis of calculation 20 years usage Yearly interest rate 5 % Recirculation System Investment 34.525 € Annual capital costs 2.769 € Annual oper. costs 3.731 € Total per annum 6.500 € Hot Water Temperature Maintenance System Investment 29.628 € Annual capital costs 2.376 € Annual oper. costs 3.453 € Total per annum 5.829 €

The Hot Water Temperature Maintenance System is the more economic choice – in every respect! The investment costs for the hot water temperature maintenance system are slightly lower than in the recirculation system Prices of metal pipes, such as copper, increased sharply last year. The use of expensive pipes provides even a greater investment cost advantage The operating costs are lower than in the recirculation system If the energy price for water heating is approx. 30% of the electricity price, the costs are equalised if the building is insulated according to the german standards An increase in efficiency means: Thicker insulation, lower heat losses, lower operating costs! Less maintenance and servicing due to the one-pipe system (fewer pipes, no control valves or pumps)

The Hot Water Temperature Maintenance System is economical and efficient Low investment costs Lower energy consumption costs No maintenance or servicing costs Economy