I am wondering if someone can help with me a problem. We have a Vaillant bolier (not sure of the model because there is no sticker but it may be one of the 800 series) and whenever we switch on the hot water, it comes on as expected and hot water comes out. However, when the water is turned off, it continually keeps switching itself on and off (there is the constant humming noise when the boilers are on, the green light keeps flashing, the yellow light goes off for few seconds, then comes on, goes off, comes on, etc...). One thing I found out by complete accident was that when we open the cold water tap, it switches off and remains off until the hot water is opened again and we are back to square one.
Can someone please shed some light on the subject? We called in a boiler "expert" and he basically said that we have a hot water leak somewhere and we need to find the leak. That was a great help. However, if that was true, then why does switching on the cold water swtiches off the boiler?
Can someone please shed some light on the subject? We called in a boiler "expert" and he basically said that we have a hot water leak somewhere and we need to find the leak. That was a great help. However, if that was true, then why does switching on the cold water swtiches off the boiler?