What it means
Si, CDi and i System Compact ErP boilers show CE with 207 under it, and the Worcester 2000 shows 207. On the Greenstar 4000 and 8000 the same problem shows as 1017 or 2971.
What to check, in order
- Read the pressure gauge
If it's below 1 bar, it needs topping up.
- Top up with the filling loop
To between 1 and 1.5 bar, following the steps in your user instructions.
- Look for leaks if it keeps dropping
Worcester's Worcester 2000 manual says to fill and vent the system and check it for leaks.
When to call a Gas Safe engineer
If you keep having to top it up, call a Gas Safe registered engineer: there may be a leak, or the pressure sensor may be faulty.
Quick answers
What does the Worcester Bosch CE 207 fault code mean?
The heating system has lost water pressure. Worcester's general advice is 1 to 1.5 bar on the gauge when the system is cool. Si, CDi and i System Compact ErP boilers show CE with 207 under it, and the Worcester 2000 shows 207. On the Greenstar 4000 and 8000 the same problem shows as 1017 or 2971.
Can I fix Worcester Bosch CE 207 myself?
Easy (about 15 minutes). Start with: read the pressure gauge; top up with the filling loop; look for leaks if it keeps dropping. If you keep having to top it up, call a Gas Safe registered engineer: there may be a leak, or the pressure sensor may be faulty.
Is Worcester Bosch CE 207 worth repairing?
Usually free. Topping up costs nothing. Doing it often means a leak that needs finding.
Checked against
- Worcester Bosch Greenstar i System Compact ErP installation instructions (PDF)
- Worcester Bosch Worcester 2000 installation and servicing instructions, document 6721814551 (PDF)
- Worcester Bosch: how often should I top up the pressure?
- Worcester Bosch: the heating system is constantly losing pressure
Last reviewed October 2026. Manufacturers update their pages, and your manual is the final word. Spotted a mistake? Email contact@appliance-error-codes.com.