This blog was started by a frustrated Vaillant owner in London, James. I am by no means a boiler engineer and have no links to Vaillant, other than being a domestic customer.
I've been supported in my efforts by my excellent installer, Alec Morrow of Integrated Heating Ltd, who has been as frustrated by this problem as me. I'm sure Alec would want me to point out that other Vaillant boilers (and indeed other makes of boiler) do no suffer from this problem, so don't be put off weather compensation altogether, which in principle is a good thing (and, as Alec never tires of pointing out, is mandatory in Germany). His enthusiasm and knowledge have been a great help. I am grateful also for the enlightening discussions with another of Alec's customers, John, who has suffered from the same problem with a 400-series boiler.
