The majority of current members are directly responsible for implementing the OpenTherm protocol; i.e. the manufacturers of controlling devices such as room thermostats and burner automations. A number of appliance manufacturers* who are responsible for implementing the OpenTherm protocol are also members of the association. Naturally, the said developments are not restricted to Dutch territory as standardization is of global significance. A list of members can be found here.
*Appliance manufacturers who apply the OpenTherm protocol do not need to be members of the association, as long as they ensure that the modules (burner automats) they use are licensed by the association. As it is important to remain in contact with these manufacturers, the association has set up a user group in order to harmonize market-oriented activities.