A Vaillant engineer has diagnosed the cause of my boiler noise to be the heat exchanger, which is what I suspected. They have taken a water sample and Fernox report says I need to first clean the system with Fernox F3 cleaner, then clean the boiler and 1 rad only with Fernox DS40, then treat the system with Fernox F1. They are happy for me to do this as long as I have proof, receipts, empty containers, they will then replace my hx. I'm quite capable of carrying this out but not sure if DS40 is compatible with my heating system?
I have a 180l flowmax thermal store on my first floor, water circulated via a pump to my boiler on the ground floor and returned to storage where it is also used to heat radiators via a second circulation pump when required. I have mains pressure hot water heated via a coil inside the thermal store, open vented system.
I've attached an image of my exact set up, no other f&e tanks or header tanks anywhere.
I have a 180l flowmax thermal store on my first floor, water circulated via a pump to my boiler on the ground floor and returned to storage where it is also used to heat radiators via a second circulation pump when required. I have mains pressure hot water heated via a coil inside the thermal store, open vented system.
I've attached an image of my exact set up, no other f&e tanks or header tanks anywhere.
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