This store is dedicated to products for integrating your boiler, heat pump, thermostat, solar or mixer module from a Bosch brand like Bosch, Nefit, Buderus, Junkers, Sieger, Worcester, elm.leblanc or iVT via MQTT or a Restful API into your home automation system like Domoticz, Home Assistant, Loxone or OpenHab.
Integration into f.i. Home Assistant is just a few clicks and you get dozens or sometimes more than 100 entities available to you. All via your local network without any cloud service.
You can read out almost every parameter and f.i. set the temperature directly from your home automation system.
I accept almost all major payment options and I ship to most countries.

Boiler and heat pump compatibility

With a few exceptions, almost all Bosch brand boilers from the last 20 years or so use the same EMS bus interface to connect thermostats, solar/mixer modules etc to the boiler/heat pump.
Depending on the brand and the protocol version, the bus is called EMS, EMS+, EMS2, ‘2-wire bus’ and Heatronic 3.
Bosch brands include Bosch, Buderus, Nefit, Junkers, Worcester, Sieger, iVT and elm.leblanc.
For heat pumps it does not matter if it is an air to water or brine heatpump, a hybrid or all-electric nor does it matter if its a split model or a Monoblock. As long as it has an EMS (or Heatronic3) bus it will be compatible.
iVT has a long history of building heat pumps, older ones do not use the EMS bus so verify it before purchase. If you are unsure whether your device is supported, just send me an email via the contact form.

Buy with confidence.
1500+ verified reviews from real customers.
BBQKees Electronics
store rating4.90 / 5
product rating4.88 / 5
1516 reviews

EMS Bus Wi-Fi Gateway

Got a new shiny heat pump or a new or existing gas boiler on your wall and you have no idea what it is actually doing?
An EMS Bus Gateway will tell you exactly that. And it can also set parameters on the fly.

An EMS Bus Gateway is a plug and play device neatly packed in a small enclosure that fits into your hand. Just plug in the device to the service jack on the boiler or heat pump with the EMS service cable and stick it to the side or inside. No additional cables are needed and everything is powered from the service jack itself.
Depending on the model they provide a wireless and/or wired networking interface.

You can try out the entire EMS-ESP demo web interface online here:
(User and password is ‘admin’.)

EMS bus interface boards

I also offer a general EMS bus to TTL serial interface board which can interface the EMS bus with an Arduino, ESP8266, Raspberry Pi etc. Sold all over Europe and beyond, this interface board is the tried and tested method to play with the EMS bus that works for basically everyone.

See the shop for all products.

Highlighted EMS products