The Baxi Z720753901 is a genuine OEM 8-litre expansion vessel designed for use in a range of Baxi, Main, and Potterton boilers between 24–33 kW output. This essential safety component maintains stable pressure within a sealed heating system by absorbing expansion of heated water, preventing pressure spikes and protecting internal boiler components.

A faulty expansion vessel can cause rapid pressure increases, leaking PRVs, fluctuating system pressure, repeated topping up, or boiler lockouts. Installing this genuine Baxi vessel restores correct pressure regulation and ensures safe, efficient heating performance.

Key Features:

• Genuine Baxi 8L expansion vessel

• Suitable for 24 kW, 28 kW & 33 kW boiler ranges

• Maintains stable system pressure during heating cycles

• Prevents over-pressurisation & PRV discharge

• Manufactured to Baxi’s strict OEM quality and safety standards

• Helps resolve pressure loss, lockouts & system instability

• Durable steel construction for long service life

• Direct-fit replacement for professional installation

Compatibility

The Baxi Z720753901 Expansion Vessel is compatible with:

• Baxi Duo-tec (24 / 28 / 33 kW)

• Baxi Platinum

• Main Eco & Eco Elite

• Potterton Promax

• Any boiler listing Z720753901 in official manufacturer documentation

Typical compatible outputs:

• 24kW

• 28kW

• 33kW

Installers should always confirm exact model compatibility using the boiler’s service manual or parts list.