Smell gas? Leave the property and call the National Gas Emergency line on 0800 111 999

F.72

Vaillant fault code

Vaillant F.72: flow or return temperature sensor fault

Engineer only

The temperature difference between the flow and return sensors is too great, which Vaillant says points to a defective flow or return temperature sensor.

What you can safely do

There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.

Call a Gas Safe engineer if

Book a Gas Safe registered engineer.

Find a Gas Safe engineer near you Opens the official Gas Safe Register search.

Applies to: ecoTEC plus. Codes can differ between models, so check your manual.

What F.72 means on each Vaillant model

From Vaillant's own fault tables. Your model name is usually on the front of the boiler or in the user manual.

Model	Meaning	Causes listed for engineers
ecoTEC plus	Flow or return temperature sensor fault	Flow/return temperature difference too great: flow and/or return temperature sensor defective

Common questions about Vaillant F.72

Can I reset F.72?

Resetting won't fix a faulty sensor. It needs a Gas Safe registered engineer.

Nearby Vaillant codes

F.22 F.28 F.75 F.29 F.83 F.23 F.20 F.25 F.27 F.61 F.62 con

See all 36 Vaillant codes