[The Gas Air Unit]
The Buderus fully modulating, low noise fan/gas valve comes factory pre-set and is controlled automatically to take precisely the amount of gas required to balance the air intake ensuring there is always a perfect gas/air mix. This enables very reliable, accurate settings and ensures total safety. Improved efficiency in this area of the boiler is the reason why Buderus 500 boilers can also offer longer flue lengths up to 35m using the 80/125mm flue giving extra siting flexibility.
