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Opentherm Converter Ems-Ot

Opentherm Converter Ems-Ot

SKU: NEF_EMS-OT_OpenTherm_converter_7746901847

In stockOrdered before 23.59, shipped today!

The Nefit / BOSCH EMS IP Converter is capable of converting OpenTherm communication Nefit / BOSCH communication protocols. This allows you to OpenTherm thermostat connected without any problems to your Nefit or BOSCH HR boiler.

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  • EAN 4051516324995
  • Condition New
  • LCD scherm No
  • Installationskills 2 Get your tools

Product information

EMS-OT OpenTherm converter Nefit

With this converter, it is possible to set your OpenTherm protocol of the boiler from closed to open. This makes it possible to link different products to the boiler. The converter is compatible with the following model boilers:


Top Line

Base Line

Pro Line

Smart Line




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  • Compatibility
    Easy to install

    Google Nest and OT converter

    Review by Andris / (Posted on 06/08/2019) RobbShop service has been fantastic. This little gadget is compatible with Heatronics 3.5 protocol as well. I was offered a full refund if it were not to work as else where Heatronics 3.0 was mentioned.
  • Easy to install

    Old Buderus boiler works with Google Nest including modulation

    Review by blahusf / (Posted on 12/03/2019) Greate product, I finally made my Buderus Logamax U124 with UBA1.5 working with Google Nest including modulation. If anybody interested in: I have Buderus Logamax U124 boiler with UBA1.5 (UBA 4001) control unit. After detective work I found out it communicates with my original RC35 thermostat via iRT protocol (not EMS as I thought). Then this OT-EMS convertor was not enough to make it work. So I bought another adapter 7736701346 Bosch CT 200 EasyControl adapter. And voila: IT WORKS!
  • Easy to install

    Plug and play

    Review by Cristian / (Posted on 17/11/2018) It is simple to install: 2 cables with 2 wires (polarity free). No configuration: it works or it does not work. Simple.
  • Quality
    Easy to install

    Excellent Product

    Review by amolines / (Posted on 13/11/2018) Excellent product, works as expected. Crystal clear instructions , easy to install
  • Easy to install


    Review by IB / (Posted on 22/06/2018) I can recommend this converter. Used for connecting my NEST 3rd gen thermostat with my JUNKERS CERAPUR SMART ( ZSB 22-3 C). Thank you for this great product, it allowed me to use the NEST thermostat and throw away the Junkers MB LAN internet gate with their horrible mobile app.
  • Easy to install


    Review by Xabi12 / (Posted on 02/10/2017) It's soon to know. It's not so cold by the moment so I didn't use it a lot. However, I can say ot was pretty usefull to connect a Nest 3td generatiom thermostat with my Junkers Heatronic i (zwbe 25/25-3c). Even inera Spain Bosch didn't know about this converter.
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EMS-OT OpenTherm converter Nefit 4051516774516


Opentherm Converter Ems-Ot

Customer Service Phone

mon-fri: 10am-5pm and sat 10am-3pm


Gerstakker 16 5236 VG Empel Netherlands

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