👋Introduction

Hello, and welcome to Sunamp's Knowledge Base and Technical Documentation Hub!

Below is a tabulated breakdown of the technical information that is available in our knowledge base for our Thermino product ranges for the US & CA markets. The purpose of this overview is to quickly help you identify the documentation that is most relevant for the application/use-case you are looking after.

ℹ️ Overview: Products, use-cases & documentation

Thermino ePlus

Thermino ePlus is a replacement for traditional direct hot water tanks, designed to provide domestic hot water for residential applications. It is powered by mains electricity and is fitted with a 3.1 kW heating element.

Thermino ePlus heat batteries are available in four sizes—20, 40, 60, and 80 US gallons—equivalent to conventional direct hot water tanks.

They are also compatible with volt-free timers, allowing users to control charging during off-peak periods and benefit from time-of-use electricity tariffs.

Thermino xPlus

Thermino xPlus is a replacement for a traditional indirect hot water tanks, designed to provide domestic hot water for residential applications. Its primary source of energy is an external heat source (such as a boiler or heat pump).

Each unit comes fitted with a 3.1 kW back-up electric heating element. This allows users to benefit from demand-side response, utilise excess solar PV where available, or provide an electric boost when needed.

For correct operation and seamless integration with external heat sources, an Optimino key (XX01) must be installed.

Thermino xPlus heat batteries are available in three sizes—40, 60, and 80 US gallons—equivalent to conventional indirect hot water tanks.

They are also compatible with volt-free timers, enabling users to schedule back-up electric charging during off-peak periods and take advantage of time-of-use electricity tariffs.

Thermino (P58)

Thermino (P58) is a replacement for traditional indirect hot water tanks, designed to provide domestic hot water for residential applications. It is heated solely by an external heat source (such as a boiler or heat pump).

Unlike other Thermino models, Thermino (P58):

Does not include a back-up electric heating element
Does not require an Optimino key for operation

Thermino (P58) heat batteries are available in four sizes—20, 40, 60, and 80 US gallons—equivalent to conventional indirect hot water tanks.

1️⃣ Application: Direct electric domestic hot water

⚡Thermino ePlus

Installation Manuals	Thermino ePlus installation & user manuals
Use-cases	Direct mains grid electricity charging Combi boiler pre-heating
Optimino keys required	NO Optimino key required
Supplementary technical notes	Thermino ePlus technical notes D0104: mandatory plumbing components D0114: cold commissioning process
Cold commissioning required?	YES - if product has been stored and transported in sub-zero temperatures (T <= 0°C/32°F) for more than 24h prior to installation. Follow document D0114 for commissioning guidance NO - if product has been stored and transported in ambient temperatures above freezing (T > 0°C/32°F). Follow standard commissioning procedure in the user manual
Mandatory plumbing components required?	YES - refer to installation & user manual and supplementary technical note D0104

2️⃣ Application: Indirect domestic hot water

Thermino xPlus

Installation Manuals	Thermino xPlus installation & user manuals
Use-cases	External heat source charging (Heat pump or Boiler) Back-up electric charging (see document D0093) Temporary continuous electric charging (see document D0116)
Optimino keys required	External heat source only charging - Optimino key type *'XX01'* required Back-up electric charging - YES Optimino key type *'XX01'* required Temporary continuous electric charging - NO Optimino key required for direct grid charging List of compatible heat sources and Optimino keys: Optimino Technology Compatible external heat sources & integration guidance: External heat source wiring & settings instructions
Supplementary technical notes	Thermino xPlus technical notes D0093: Thermino xPlus in back-up electric mode D0104: mandatory plumbing components D0114: cold commissioning process D0116: Thermino xPlus in temporary continuous electric mode
Cold commissioning required?	YES - if product has been stored and transported in sub-zero temperatures (T <= 0°C/32°F) for more than 24h prior to installation. Follow document D0114 for commissioning guidance NO - if product has been stored and transported in ambient temperatures above freezing (T > 0°C/32°F). Follow standard commissioning procedure in the user manual
Mandatory plumbing components required?	YES - refer to installation & user manual and supplementary technical note D0104

Thermino (P58)

Installation Manuals	Thermino (P58) installation & user manuals
Use-cases	External heat source charging only (Heat pump or Boiler)
Optimino keys required	NO Optimino key required
Supplementary technical notes	Thermino (P58) technical notes D0104: mandatory plumbing components D0114: cold commissioning procedure
Cold commissioning required?	YES - if product has been stored and transported in sub-zero temperatures (T <= 0°C/32°F) for more than 24h prior to installation. Follow document D0114 for commissioning guidance NO - if product has been stored and transported in ambient temperatures above freezing (T > 0°C/32°F). Follow standard commissioning procedure in the user manual
Mandatory plumbing components required?	YES - refer to installation & user manual and supplementary technical note D0104

Thermino documentation hub overview (US/CA)