What is a Sunamp Thermino? (a.k.a Thermal Battery)

Created by Jack Murphy, Modified on Thu, 31 Jul at 2:09 PM by Jack Murphy

Thermal batteries or Heat batteries work upon the same premise as solar batteries - they take unused energy and store it for later use. The difference with thermal/heat batteries are:

  • They are able to use thermal energy as well as electricity to store their energy.
  • They can reverse the storage process to heat up cold water

  • They are typically used in place of a hot water tank on standard (not combi) boiler systems or with Heat Pumps


The prevalent brand of thermal batteries in Europe would be Sunamp with their Thermino models. Inside they use a phase change material (PCM) which absorbs and releases thermal energy during a melting and freezing process in a similar way to the gel in a pocket handwarmer. A high-powered heat exchanger or heating element immersed inside of the PCM rapidly charges the thermal battery and just as rapidly reverses the process for mains pressure hot water straight from the stored energy.


Working with Sunsynk Inverters


The Thermino models can be charged from 3 sources:

  • Hot water produced by a boiler/heat pump
  • Electricity from the grid
  • Electricity from Solar PV - typically requires an Optimino Key


Optimino Keys are small control modules which plug into the Sunamp Thermino and can instruct it to power from different sources such as a solar PV system.


There are two models of Thermino, the 'e' models which are a relplace a direct hot water cylinder and the 'x' models which replace an indirect hot water cylinder (used more with Heat Pumps). The ePlus model would use the PV02 Optimino key when being paired with solar, including Sunsynk inverters. The xPlus model typically requires an Optimino key specific to the brand of Heat Pump manufacturer but should still work with solar PV. Refer to Sunamp product manual or Support for wiring diagrams and up-to-date details of Optimino Key requirements.







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