How Old is My Boiler - Tell the Age of Vaillant o
How Old is My Boiler: Baxi. Depending on the age, a Baxi boiler will have a seven, twelve or fourteen-digit serial number. Luckily, the manufacture year is always the fourth and fifth characters. For example this serial number: BCP051100298ZX. means the boiler has been made in 2005. If you run into problems, you can check this page for reference.