Does Bosch EasyControl work with my boiler? Per brand: directly, with an adapter or not at all

Short answer: the Bosch EasyControl is an EMS bus thermostat. On a Nefit or Bosch boiler with EMS bus (TrendLine, ProLine, TopLine, BaseLine, SmartLine, 9000i, 2300i, 1200, Bosch HRC II/HRS II, Condens 3000W/6000W, Compact) sluit u hem directly . On a boiler from a different brand (Intergas, Remeha, ATAG, Vaillant and others) and on older Nefit boilers (ProLine NxT, EcomLine, Economy) it works only with the EasyControl Adapter: modulating with OpenTherm, on/off only with an on/off boiler. Below, per brand, what you need and the current price. Which set to buy: Bosch EasyControl kopen: welke set heb ik nodig?

Three situations

Your boiler	Does EasyControl work?	What you need	Modulating?
Nefit or Bosch with EMS bus (EMS 1.0 or 2.0, HT3)	Yes, directly	Only the thermostat	Yes, with readout of pressure and consumption
Other brand with OpenTherm (Intergas, Remeha, ATAG, Vaillant with VR 33, AWB and others)	Yes, with adapter	Thermostat + EasyControl Adapter (or the set)	Yes; water pressure only if the boiler has a pressure sensor
On/off boiler (older appliance without OpenTherm) or district heating	Yes, with adapter	Thermostat + EasyControl Adapter	No: on/off only, no readout
Nefit ProLine NxT, EcomLine, Economy (iRT protocol)	Yes, with adapter	Thermostat + EasyControl Adapter	Ja
Bosch HRC I, HRC Top, HRS Top	With adapter, if the OTM1 module is present	Thermostat + adapter; installer checks the OTM1	Ja

Per brand

Brand	Boiler protocol	EasyControl	Guide
Nefit	EMS bus (modern series) or iRT (ProLine NxT, EcomLine, Economy)	Direct	Nefit and Bosch per series
Bosch	EMS-bus (HRC II, HRS II, Compact, Condens 3000W/6000W)	Direct	Nefit and Bosch per series
Intergas	OpenTherm	With adapter	Intergas
Remeha	OpenTherm (Ace series also R-bus)	With adapter	Remeha
ATAG	OpenTherm	With adapter	ATAG
Vaillant	eBus; OpenTherm only with the VR 33 module	With adapter and VR 33, otherwise on/off	Vaillant
AWB, Ferroli, Itho Daalderop, Viessmann and others	Usually OpenTherm or on/off; stated in the installation manual	With adapter	Look under "thermostat connection" in the manual

What you need, with current price

Step by step: connecting EasyControl

Always read your boiler's installation manual first. If you are unsure about the terminals, have an installer do it.

1. Disconnect the boiler from the power (unplug it) and disconnect the existing thermostat. Bosch specifies that only one thermostat may be connected to the boiler.
2. Connect the EasyControl Adapter with two wires to the boiler's thermostat terminals (the OpenTherm terminals on OpenTherm boilers, the on/off contact on on/off boilers). The adapter needs its own power socket.
3. Connect the EasyControl thermostat with two wires to the adapter (no polarity).
4. Order when switching on: first the thermostat, then plug the adapter into the socket, then the boiler. The adapter searches for OpenTherm for about a minute; if it does not find it, it switches to on/off. To make it search again: unplug the adapter for 25 seconds.
5. Switch the boiler on, connect to your 2.4 GHz Wi-Fi via the Bosch EasyControl app (5 GHz does not work) and follow the setup.
6. After half an hour, check whether the boiler modulates (the flame keeps burning at lower output) and whether the app shows the boiler status.

Things to bear in mind

• On/off via the adapter: the boiler does not modulate and the app reads nothing (no water pressure, no consumption). You do keep remote control, the time programme and presence detection.
• OpenTherm via the adapter: modulating. The water pressure is only shown if the boiler has a pressure sensor and the values have been checked once.
• Nefit Easy Connect or RCC module on an older boiler: remove it first, EasyControl does not work together with it.
• One EasyControl per boiler. You control multiple rooms with the Smart Radiator Thermostats (radiator heads), not with a second thermostat.
• 2.4 GHz Wi-Fi is required; a network that only broadcasts 5 GHz does not work.

Controlling multiple rooms separately

With Bosch's Smart Radiator Thermostats you control the temperature per radiator from the same app. This also works with the adapter. The sets with 2 or 4 radiator heads are intended for Nefit/Bosch boilers; for another brand, order the adapter separately. With low-temperature radiators the desired temperature must be set high enough, otherwise the heads close too early (maximum setting 30 °C).

Frequently asked questions

Is the Bosch EasyControl an OpenTherm thermostat?

No. The EasyControl speaks EMS bus, the Nefit and Bosch protocol. With the EasyControl Adapter it translates to OpenTherm (modulating) or to an on/off contact.

Do I need an adapter for a Nefit TrendLine or ProLine?

No. TrendLine, ProLine, TopLine, BaseLine, SmartLine, 9000i, 2300i and 1200 have EMS bus and work directly. Only the ProLine NxT, EcomLine and Economy need the adapter.

Can I connect the EasyControl to an Intergas, Remeha or ATAG?

Yes, with the EasyControl Adapter on the OpenTherm terminals. The boiler then modulates as normal. You buy the thermostat and the adapter separately, or the set with adapter.

Does EasyControl work on a Vaillant ecoTEC?

Vaillant uses eBus. EasyControl only works modulating if the boiler has a VR 33 OpenTherm module, plus the EasyControl Adapter. Without VR 33, only on/off remains. A Vaillant eBus thermostat is then often the simpler choice.

What do I lose with an on/off connection?

Modulation and readout: the boiler fires at full output until the temperature is reached and the app shows no water pressure or consumption. Remote control, time programme and presence detection keep working.

Does Instalpunt check whether the thermostat fits my boiler?

No. We supply the product and indicate which protocol works. Whether your specific appliance has OpenTherm, EMS or on/off is stated in the boiler's installation manual; if in doubt, ask the manufacturer or your installer.

Other brands

• EasyControl on a Nefit or Bosch boiler
• EasyControl on an Intergas boiler
• EasyControl on a Remeha boiler
• EasyControl on an ATAG boiler
• EasyControl on a Vaillant boiler

More about thermostats: thermostat not responding en all thermostats in the webshop.

Sources: Bosch brochure "Is EasyControl geschikt voor mijn verwarmingssysteem?" (document number 6721867369, October 2024) and the page about the EasyControl Adapter on nefit-bosch.nl. Protocols of other brands: manufacturers' installation manuals. Page updated: 12 October 2026.