Worcester Bosch E133 Fault Code On Boiler: Causes & Fixes
If your Worcester Bosch boiler is showing an E133 fault code, it usually means the boiler has lost gas supply or gas pressure during ignition. The boiler has locked out because it couldn’t confirm a safe gas supply to fire up correctly.
We’re Hinckley Plumbing & Heating, established and professional Gas Safe registered engineers covering Hinckley, Nuneaton, Leicester, Tamworth, Coventry, Rugby, and Loughborough — and this guide explains what the Worcester Bosch E133 fault code means, what causes it, what you can check yourself, and when to call us if you need a boiler repair or a replacement boiler.
What Does The Worcester Bosch E133 Fault Code Mean?
The Worcester Bosch E133 fault code is a gas supply fault. It appears when the boiler detects that gas pressure has dropped or been interrupted during the ignition process, so it locks out as a safety precaution.
What Is The Worcester Bosch E133 Fault On A Boiler?
The Worcester Bosch E133 fault on a boiler means the boiler couldn’t maintain a stable gas supply long enough to ignite and run safely. This is often linked to the gas meter, the gas valve, or supply issues further upstream rather than a fault within the boiler itself.
What Causes A Worcester Bosch E133 Fault Code?
The most common causes of a Worcester Bosch E133 fault code are:
- The gas supply to the property being temporarily interrupted
- Low gas pressure from the meter, especially after a meter exchange
- Air in the gas line after supply work nearby
- A faulty gas valve within the boiler
- The gas supply being switched off, either deliberately or by a prepayment meter running out
Can I Reset A Worcester Bosch E133 Fault Code Myself?
Yes, this is usually the first thing to try, especially if you know the gas supply was recently interrupted. If the fault clears and doesn’t return, the cause was likely a temporary supply issue. If it comes straight back, there’s a more persistent gas supply or valve problem.
How To Fix A Worcester Bosch E133 Fault Code On A Boiler
If you’re confident doing so, you can try the following before calling an engineer:
- Check that your gas supply hasn’t been cut off, including checking a prepayment meter if you have one.
- Confirm other gas appliances in the home are also working.
- Turn the boiler off, wait a few minutes, then attempt a reset.
- Check the boiler display to see if the fault code clears after reset.
- If the fault returns immediately, stop attempting resets and call a Gas Safe registered engineer.
Why Does The Worcester Bosch E133 Fault Code Keep Coming Back?
If the Worcester Bosch E133 fault code keeps returning after resetting and you’ve confirmed the gas supply is fine, the fault is more likely linked to a faulty gas valve or internal component rather than an external supply issue.
When Should You Call Us About A Worcester Bosch E133 Error Or Fault?
Call Hinckley Plumbing & Heating if:
- The E133 fault code returns immediately after resetting
- You’ve confirmed the gas supply is on and other appliances are working
- You can smell gas near the boiler
- The boiler won’t hold ignition even briefly after resetting
- You’ve reset the boiler more than once without success
Those signs usually mean the Worcester Bosch E133 boiler fault needs proper diagnosis rather than repeated resets.
Book A Worcester Bosch Boiler Fault Check
If your Worcester Bosch boiler is showing an E133 fault code, we can help. We cover Hinckley, Nuneaton, Leicester, Tamworth, Coventry, Rugby, and Loughborough, and we’ll give you a clear, honest assessment of whether it’s a supply issue or an internal gas valve fault. Call us or use our contact form to book a boiler inspection.
Worcester Bosch E133 Fault Code FAQs
Is the Worcester Bosch E133 fault code dangerous?
The fault is a safety lockout to prevent unsafe ignition, so it’s not dangerous on its own, but if you smell gas you should turn off the supply if it’s safe to do so and call the National Gas Emergency Service on 0800 111 999 immediately.
Can a prepayment meter cause an E133 fault code?
Yes, if the credit has run out and the gas supply has been cut off, the boiler can show an E133 fault code as it loses gas pressure.
Why does my Worcester Bosch boiler keep showing E133 after I reset it?
If the gas supply is confirmed to be working, a recurring E133 fault usually points to a faulty gas valve or internal component needing replacement.
Will resetting my boiler clear the E133 fault permanently?
If the cause was a temporary supply interruption, yes. If it returns repeatedly, resetting alone won’t resolve the underlying fault.