If you’re planning to install a Sunamp heat battery, you’re already on your way to a highly efficient, space-saving hot water solution. To get the best performance and ensure a smooth installation, it’s important to understand which additional components you may need and why.

Understanding your Sunamp model

There are three different ranges of Sunamp model to choose from, and the components you need will depend on which one you’re installing: Thermino ePlus, Thermino xPlus, or Thermino TS.

Each does have slightly different requirements, but there are some shared essentials that apply across all installations.

Thermino ePlus

Every ePlus installation requires the A2057 installation kit, also known as the Heat Battery Protection Kit. This kit contains the following:

• 1 x Inlet control group (pressure reducing valve, non-return valve, and expansion relief valve)
• 1 x Thermostatic mixing valve (C5388)
• 1 X 2.0L expansion vessel
• 1 x Isolation valve

 

The installation kit helps protect the unit, ensures safe operation, and is recommended by Sunamp.

You also need to consider your water quality. If you are installing the unit in a hard water area, you’ll need a water conditioner such as the Hydroflow HS38. Hard water can cause limescale build-up inside the Sunamp over time, which reduces efficiency and can shorten the lifespan of the unit. Installing a Sunamp in a hard water area without a water softener can void the warranty if damage to the unit is caused by mineral build up.

If you’re unsure whether you’re in a hard water area, the easiest way to check is on your water supplier’s website. Most UK utility providers have a section where you can enter your postcode and see the hardness level of your water.

If you’re planning to charge your Sunamp Thermino ePlus using solar PV, you’ll also need the PV02 PV key. This enables the Sunamp to accept and store surplus solar energy, helping you maximise self-consumption and reduce your energy bills.

To get the most out of a solar-connected Sunamp system, we recommend also adding a myenergi eddi and harvi. These devices work together to divert excess solar generation into your hot water system efficiently, improving overall performance and further reducing your reliance on grid electricity.

It’s worth noting that a Sunamp unit has no built-in controls for scheduling when it charges. If you’re installing a ePlus model that will be charged from the grid only (without solar), we strongly recommend adding a volt-free timer. This will allow you to control when the Sunamp charges, which can be vital if you’re on a time-of-use tariff such as Economy 7. By setting your Sunamp ePlus to charge during off-peak hours, you can significantly reduce running costs. Volt-free timers are widely available from most trade counters and are a simple but effective addition to your system.

Thermino xPlus

The Thermino xPlus range is more flexible, and should be used in systems that include heat pumps or boilers, with the option for solar PV as well.

Like the ePlus, xPlus installations also require the A2057 installation kit, and may require a water conditioner if you are installing the unit in a hard water area.

Where the xPlus differs is in how it integrates with other technologies. To enable this, you will need the correct Optimino key.

If you’re installing your xPlus alongside a heat pump, you’ll need the key designed specifically for that model of heat pump. If your system includes both a heat pump and solar PV, you’ll need a different key that supports both inputs.

It is also possible to pair an xPlus unit with a boiler. If you’re installing a xPlus unit alongside a boiler without solar PV, you’ll need the VF01 key. If you’re installing a xPlus unit with a boiler and solar PV, you’ll need the VF02 key.

As there are several different keys available for xPlus models depending on your setup, it’s important to check the details carefully before purchasing.

Thermino TS

The Thermino TS range is designed as a more straightforward hot water solution, with no need for Optimino keys. It can pair with boilers and heat pumps seamlessly, often used as a direct replacement for traditional cylinders.

TS units do still require the A2057 installation kit, and water quality still matters. If you live in a hard water area, a Hydroflow water conditioner is strongly recommended to protect your investment and maintain long-term performance.

Choosing the right components for your Sunamp installation

Every Sunamp installation is slightly different, depending on your property, water quality, and which energy source(s) you’re integrating.

If you’re unsure about what you need, it’s worth speaking to a professional. Choosing the correct components at the outset will ensure your system runs efficiently, reliably, and exactly as intended.

Your installer may also recommend certain valves or fixings, but these are generally standard plumbing considerations rather than Sunamp-specific accessories.

ePlus components (without solar)

Sunamp Heat Battery Protection Kit 

HydroFLOW Pearl Electronic Water Conditioner

ePlus components (with solar)

Sunamp Heat Battery Protection Kit 

HydroFLOW Pearl Electronic Water Conditioner

Optimino PV Key PV02

myenergi Eddi

myenergi Harvi

xPlus components 

Sunamp Heat Battery Protection Kit 

HydroFLOW Pearl Electronic Water Conditioner

VF01 Boiler Key

VF02 Boiler + PV Key

Compatible heat pump brands	Without solar PV	With solar PV
Amitime PAVH-08V1GFB R290 HP	AE01	AE02
Bosch Compress 5800i AW R290	BH01	BH02
Daikin Altherma 3HHT R32 series	DN01	DN02
Ecoforest ecoAIR PRO series Ecoforest ecoGEO PRO R290 series	ET01	ET02
Grant Aerona HPR290 series	GT01	GT02
Haier Monobloc GT R290 series	HR01	HR02
Hisa HR290	HA01	HA02
Hisense Hi-Therma R290 Monobloc	HE01	HE02
Ideal HP290 R290 Monobloc	IL01	IL02
LG Therma V Monobloc RS90 series	LG01	LG02
Midea MHC R290	MA01	MA02
Mitsubishi Electric PUZ-WZXXVAA R290	MC01	MC02
NIBE S2125 R290	NE01	NE02
Panasonic L series R290	PC01	PC02
Phnix Greentherm R290 series	PX01	PX02
Samsung EHS HTQ R32 series Samsung EHS Mono R290	SG01	SG02
Stiebel Eltron WPL-A 07 HK 230 Premium R454C HP	SL01	SL02
Tongyi R290 Inverter Series 'TAHMV-R'	TI01	TI02
Trianco Activair R290 series	TO01	TO02
Vaillant Arotherm + R290 series	VT01	VT02
Viessmann Vitocal R290	VN01	VN02