Hot Water Maintenance Controller HWAT ECO v5

The domestic hot water supply can be designed as a single pipe system (no return pipes or recirculation pumps, no hydraulic balancing required) fitted with an energy efficient, self-regulating temperature maintenance cable system to compensate for heat losses and to maintain pipe temperatures.

The domestic hot water supply can also be designed as a hybrid system, with recirculation loops on the main supply pipes optimized by the use of a self-regulating temperature maintenance cable system on all branch pipe run outs. Providing the convenience of instant hot water, the Raychem HWAT system keeps water at the right temperature in a building’s water distribution pipe work. No return pipes or recirculation pumps are fitted and no hydraulic balancing is required.

To compensate for heat losses and to maintain pipe temperatures, all hot water supply pipes are fitted with an energy efficient self-regulating heating cable system (Raychem HWAT). The system is complete with self-regulating temperature maintenance cables, an advanced energy efficient controller and cold applied components for interconnection and termination.

System components:

• Self-regulating temperature maintenance cable.
• Cold applied insulation displacement components, for interconnection.
• Cold applied, gel-filled end seal.
• Single circuit, single application energy efficient controller.
• Multi circuit, single application control panel with integrated energy efficient controller.
• Multi circuit, multi-application distributed control and monitoring system with integrated energy efficient controller.

Self-regulating temperature maintenance cable (HWAT):

The self-regulating temperature maintenance cables are specifically designed, tested and approved to IEC 62395:2013 and IEEE 515.1, suitable for use with 20 A circuit breakers and with a minimum bend radius ≤10 mm.

The cable includes a conductive polymer core (qualified for hot water temperature maintenance), modified polyolefin electrical insulation (radiation cross-linked, to ensure long life expectancy), laminated aluminium foil layer (to protect the heater core from chemical ingress), tinned copper braid with minimum 70% coverage and modified polyolefin over jacket printed with cable model, batch number and metre marks.

Cold applied interconnection and termination components (RayClic):

Interconnection and termination via cold applied insulation displacement connectors and gel type end seals, which are UV resistant, IP68 and 65°C rated, suitable for 2 500 VDC insulation resistance test, with Torx head fittings for ease of installation and both audible and visual installation confirmation.

Thermal insulation:

Insulation selection and thickness are strictly in accordance with the self-regulating temperature maintenance cable system design guide, with variations in ambient temperature fully considered.

Approvals and warranty:

The temperature maintenance cables, controls and system components are CE marked and certified according to EN codes by BSI, VDE, CSTB, SEV, OVE and fulfil the hygiene requirements of DGVW and SVGW.

Single circuit, single application energy efficient controller:

All self-regulating hot water temperature maintenance circuits are controlled with an energy saving, programmable, single circuit local controller to provide adjustable maintained temperatures in the range 50-65°C (HWAT ECO).

Multi circuit, single application control panel with integrated energy efficient controller:

All self-regulating hot water temperature maintenance circuits are controlled and monitored using an energy saving, programmable, electrically protected, multi-circuit control panel (SBS-xx-HV-EC0-10), complete with integrated energy efficient controller (HWAT ECO).

Multi circuit, multi-application distributed control and monitoring system with integrated energy efficient controller:

All self-regulating hot water temperature maintenance circuits shall be controlled and monitored using a centralized control system with distributed power and control modules (ACS-30), complete with integrated energy efficient controller (HWAT ECO). The centralized control system provides pre-programmed parameters to provide concurrent control for hot water temperature maintenance, pipe freeze protection, flow maintenance, surface snow melting, roof and gutter de-icing and floor heating applications.

The domestic hot water supply has been designed as a single pipe system, no return pipes or recirculation pumps shall be fitted and no hydraulic balancing is required. To compensate for heat losses and to maintain pipe temperatures, all hot water supply pipes shall be fitted with an energy efficient self-regulating heating cable system. The system shall be complete with self-regulating temperature maintenance cables, advanced energy efficient controller and cold applied components for interconnection and termination.

Electrical connection:

• Supply voltage: 230 V a.c./ 50 Hz.
• Connections between the electrical supply, control panel and trace heating circuits shall be installed by an approved electrical contractor
• Circuit breaker protection required by MCB (BS EN 60898 type C or D). Residual current device required, RCD (30 mA sensitivity, tripping within 100 ms). Maximum approximately 500 m of self-regulating heating cable can be monitored per RCD.

Design:

The manufacturer shall be able to provide all design calculations, including heat loss and corresponding selection of heating cables; electrical schedules providing cable lengths, circuit breakers, circuit start up currents, operating currents and loads, line list summary and single line details; system layout and schematic drawings indicating power connections, tees and end seals; controller configuration listing and wiring diagrams.

Installation:

All temperature maintenance cables shall be installed in accordance with the design plans, within the defined maximum circuit lengths, tested and commissioned strictly in accordance with the manufacturer’s instructions (IM-CDE1547) using a 2500 Vdc megger. Thermal insulation shall be closely coordinated with the responsible sub-contractors and follow the specific design schedules. ATE-180 shall be used on plastic pipes.

Features and benefits:

• Less water volume and less heat loss in the pipe work help prevent bacteriological problems.
• A flexible and space saving system, no return pipes.
• The heating cable is simply fixed on the supply pipe.
• The heat loss in the system is significantly lower as only the heat loss from the feed pipe is to be compensated for, there is also no power requirements for circulation pumps.
• Suitable for use with smaller boilers as there is no cold return, the water heat-up is more efficient.
• The intelligent HWAT-ECO control unit saves power as it can lower the temperature or switch off during water consumption peaks.
• The system has no mechanical parts to wear out.
• The self-regulating Raychem heating cable has a demonstrable useful lifetime of over 40 years.