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

Worcester Bosch fault code

Worcester Bosch A7: hot water temperature sensor defective

Engineer only

Worcester Bosch describes A7 on Greenstar CDi Classic boilers as: hot water temperature sensor defective.

What you can safely do

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

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

Applies to: Greenstar CDi Classic. Codes can differ between models, so check your manual.

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

Model	Meaning
Greenstar CDi Classic	Hot water temperature sensor defective

Can I fix Worcester Bosch A7 myself?

No. It needs a Gas Safe registered engineer to diagnose. Tell them the exact code and your boiler's model name.