Low
d.36 on Vaillant ecoTEC Plus 836

This code is simply showing you a live readout of how much hot water is currently flowing through your boiler and is not an error message.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Value for the hot water flow: Current value in l/min

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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