Viessmann Manifold Return DHW Heat Exchanger 7828037

The Viessmann 7828037 is a return manifold for the domestic hot water (DHW) heat exchanger, listed by the manufacturer as MANIFOLD (RETURN, DHW HEAT EXCHANGER). It sits in the DHW circuit of Vitodens 111-W, 222-F and 242-F family appliances, where it returns water through the heat exchanger. It is catalogued within the isolation valve group of Viessmann boiler spares.

• Water weeping or a visible drip from the manifold body or its connections
• Corrosion, verdigris or limescale build-up around the manifold and heat exchanger joints
• Reduced or inconsistent hot water temperature at the tap
• Staining or crusting on adjacent components indicating a long-standing leak

• Confirm the appliance model and serial number against the fits list, as several Vitodens variants use different return assemblies
• Check the serial plate on the boiler before ordering where similar model names appear more than once
• Inspect the existing manifold connections and pipework for damage before fitting
• Consider whether the isolation valve on the return side also needs replacing at the same time