Sunamp installation guide (for installers)

Sunamp heat batteries are compact thermal stores using a phase change material to provide hot water on demand. They can replace conventional hot water cylinders and are compativle with mains electricity, heat pumps, boilers and solar PV systems.

This installation guide is intended for qualified personnel familiar with UK plumbing, unvented hot water systems, and electrical installations. All work must comply with relevant building regulations, water regulations and electrical standards.

Pre-installation requirements

Qualifications

Sunamp units must be installed by a competent installer. While no specific course is mandated by the manufacturer, installers should have all relevant qualifications, training and experience to install unvented hot water systems and electrical heating equipment.

Sunamp do offer free installer training which covers handling, siting, plumbing, wiring and commissioning. Completing this training and certification can support technical competence and warranty compliance.

System components

Before installation, ensure you have all required components and accessories:

•          Sunamp Thermino heat battery
•          Mandatory hydraulic protection components (see below)
•          Isolation valves for maintenance
•          Thermostatic mixing valve (TMV) for scald protection
•          Appropriate fixings and pipework materials
•          Control and wiring components specific to model and system design

Sunamp’s installation manuals include detailed product specifications, dimensional data and step-by-step installation instructions for each Thermino variant.

Mandatory plumbing components

To protect the heat battery and comply with warranty requirements, install the following mandatory plumbing components in all direct and indirect systems:

•          Heat battery isolation valve
•          Mains cold water pressure reducing valve (PRV)
•          Mains expansion relief valve (ERV)
•          Expansion vessel or shock arrestor
•          Hot water thermostatic mixing valve (TMV)
•          Water conditioner in hard water areas (where scale risk is present)
•          Auto-bypass valve (indirect models only)
•          Primary circuit expansion vessel (indirect models only)

Failure to install these components correctly can cause heat battery damage and invalidate manufacturer warranty.

Follow the Sunamp technical note on mandatory plumbing components in conjunction with the specific installation manual for the model being installed.

Siting and positioning

Choose an installation location that provides safe and easy access for plumbing and electrical work, protects the unit from freezing temperatures and direct moisture, allows compliance with ventilation and service clearance requirements, and facilitates connection to mains cold, hot outlets and control wiring.

Sunamp units can often be installed in confined spaces such as utility cupboards due to their compact footprint, but always check clearances shown in the product manual.

Plumbing connections

Connect the cold mains water supply directly to the inlet of the heat battery. The hot outlet must be piped to the dwelling distribution system. Key plumbing requirements:

•          Use appropriate pipe materials and fittings for mains pressure
•          Install all protection and regulation valves before and after the unit
•          Ensure correct orientation of valves and flow direction
•          Include isolation points for servicing

The hot water delivery from the heat battery will be at a higher temperature before tempering, so a thermostatic mixing valve must be installed at the outlet to prevent scalding.

Indirect models will require connections to primary circuits (boiler or heat pump), including correct bypass and expansion components.

Electrical installation

Electrical connections must be completed by a qualified electrician in accordance with current wiring regulations.

•          Check unit rating and supply requirements from the product manual
•          Provide a dedicated circuit and appropriate protective devices
•          Follow Sunamp wiring and settings documentation for model-specific controls
•          Ensure control wiring for timers, smart controls and PV diversion devices is correctly terminated

Some variants have specific wiring configurations for solar PV diverters, Optimino controllers and heat pump integration, install per the relevant wiring manual.

Solar PV and heat pump integration

For installations paired with solar PV, use a compatible diverter (eddi or similar) or energy management system. Configure the PV charge settings according to manufacturer instructions, and use the Sunamp wiring and settings manual specific to PV models.

For heat pump connected systems, follow the Thermino xPlus heat pump specific wiring and system diagrams. Ensure the primary heat pump circuit and heat battery circuit are piped per design.

Refer to the manufacturer’s wiring guides for PV and heat pump configurations for model-specific details.

Commissioning procedure

Once plumbing and electrical works are complete:

•       Verify all mandatory protection components are installed
•       Pressurise the system and check for leaks
•       Energise the electrical supply and confirm the unit enters its charging mode
•       Test hot water delivery through the internal heat exchanger
•       Verify the thermostatic mixing valve operation and final delivery temperatures
•       Complete any model-specific commissioning steps as directed in the unit’s manual

Sunamp installation manuals provide commissioning checklists and certificates for installer sign-off.

Documentation and support

Installers should always consult the official Sunamp installation manuals, technical notes and system diagrams.

These contain model-specific details such as dimensions, wiring diagrams, pressure settings and full hydraulic schematic requirements.