Author: Jayesh Kanbi (MD, MyBoiler Ltd)
There are approximately several milllion condensing Vaillant and Worcester Bosch boilers, of which have the abilitity, to have modulating controls that would save on energy bills and create a much more reliable heating system. See our modulating controls article for more info. Currently these two manufacturers do not allow other controls, officially, to be connected to your boiler to take advantage of this form of control.
Their actions convey, that they intend to lock you into using their own controls, or a standard that is not so widely adopted. As reported by them, their own controls may work better with their boilers, as they take advantage of all the features, however a single choice of controls would be considered anti-competive behaviour, especially as the uk government is trying to reduce energy usage for future key targets. This also goes against you as home owners and bill payers intending to reduce your energy bills.
These two manufacturers have created OpenTherm adapters in the Netherlands, as it has been required by the government as a compulsory measure. These adaptors have imported by us, and several other engineers, into the UK. They have been tested and have worked with success, with no known problems to date. See our page on OpenTherm Capable Boilers to find our more about these boilers and adaptors.
The problem is that the manufacturers have stated that if these adaptors are used here in the UK, that your warrantee will be void. So what they are essentially saying is their own parts, created for their own boilers in Europe, which are essentially the same electronically, are not allowed in the UK, even though it could lead to substantial energy savings, reliability and enhanced efficiency.
We propose and instruct the UK government to allow these adaptors to be used here in the UK legally without the threat of warrantee or guarantee being cancelled or void, so that home owners or tenants with OpenTherm thermostats, such as Nest Third Generation and Honeywell Lyric can control these boilers more efficiently than currently possible with standard on/off controls. See OpenTherm Compatible Controls at the bottom section of OpenTherm Capable Boilers page.
Whilst we would like to adaptors to be legalised, we would go so far as saying, that optimistically these interfaces should be incorporated onto all new boilers and at minimum be provided with the boiler.