Medium
E33 on Ariston Euro Combi 30 MFFI

Your boiler has stopped because it thinks a safety switch connected to your underfloor heating has been triggered or disconnected.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Floor heating thermostat open circuit (if fitted) (ROOM THERMOSTATFLOOR)

From this model's manual
Verified against the Ariston/Ariston Euro Combi 30 Mffi 4711645 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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All 30 fault codes on the Euro Combi 30 MFFI

Seeing a different code? Every code this model can display, in one place.

0506A 18A 37A 39A 40A 41A01A03E 05E 06E 07E 08E 09E 10E 11E 12E 13E 14E 15E 16E 20E 29E 37E 38E02E04E18E30

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