Vaillant Diaphragm Kit 01-0365 Was 01-0357 010365

Diaphram Kit Vaillant

The Vaillant Diaphragm Kit 01-0365 (formerly 01-0357) is a genuine OEM replacement kit designed for use in Vaillant boilers to maintain correct operation of the water section and pressure differential assembly. The diaphragm regulates water pressure and flow within the boiler’s diverter or hydraulic system, ensuring consistent heating and reliable hot water performance.

Manufactured from high-grade, heat- and pressure-resistant rubber, the 010365 diaphragm maintains flexibility under continuous system load and prevents operational faults caused by pressure imbalance or water leakage. This replacement kit is an essential maintenance component to restore stable boiler functionality and prevent flow-switch issues.

Key Features

• Genuine Vaillant diaphragm kit – Part No. 01-0365 (replaces 01-0357)

• Maintains correct water pressure and flow regulation

• Prevents loss of heating or hot water due to diaphragm failure

• Made from durable, heat-resistant elastomer

• Direct OEM-quality replacement – perfect fit and reliable seal

• Suitable for use in domestic Vaillant combination and system boilers

• Ensures consistent performance and long service life

Compatibility

• Fits a wide range of Vaillant boiler models

• Replaces previous part number 01-0357

• Commonly used in ecoMAX, TURBOmax, and older VCW series boilers

• Compatible with hydraulic water section / diverter valve assemblies

When to Replace

• If the boiler loses pressure or hot water intermittently

• When the existing diaphragm is torn, brittle, or deformed

• During boiler service or diverter valve overhaul

Technical Specifications

• Manufacturer: Vaillant

• Part Numbers: 01-0365 / 010365 (was 01-0357)

• Component Type: Diaphragm kit

• Material: Reinforced heat- and pressure-resistant rubber

• Function: Controls pressure and flow in hydraulic assembly

• Application: Domestic combination and system boilers