Buderus fault code OF-
Fault code OF- on a Buderus boiler (including Logamax plus GB402-320 G20 and Logamax plus GB402-320 G25) means: Insufficient flow through the boiler. Max. temperature difference between flow and return > 15 K Temperature difference between flow and safety temperature sensor > 15 K. Reset the appliance once. If the code comes back, a part is usually faulty, often a temperature sensor.
After a safety alert (gas, flue gas, combustion), reset no more than once and call in a certified gas engineer. If you smell gas, call your national gas emergency number or 112 immediately.
Cause
Fault code OF- on a Buderus boiler indicates: Insufficient flow through the boiler. Max. temperature difference between flow and return > 15 K Temperature difference between flow and safety temperature sensor > 15 K.
Applies to
Buderus Logamax plus GB402-320 G20, Logamax plus GB402-320 G25, Logamax plus GB402-395 G20, Logamax plus GB402-395 G25, Logamax plus GB402-470 G20, Logamax plus GB402-470 G25, Logamax plus GB402-545 G20, Logamax plus GB402-545 G25, -.
Matching parts
Buderus parts are available from Instalpunt; shipping to EU countries from €17.95 (€24.95 for more distant countries), usually 3–5 working days.
To fix this fault you often need a replacement part. View the available Buderus parts:
Further reading on this cause
Other Buderus codes with the same cause
- 0Y 276 — The flow temperature sensor has measured a temperature higher than 95°C.
- 0Y 277 — The safety temperature sensor has measured a temperature higher than 95°C.
- 0Y 285 — The return temperature sensor has measured a temperature higher than 95°C.
- 1C210 — The flue gas sensor has measured too high a temperature and is open.
- 2F260 — The flow temperature sensor measures no temperature rise after a burner start.
- 2F271 — The heating water temperature difference measured between the flow and safety temperature…
Fix it yourself or call an engineer?
Always consult the manual for your appliance and work safely. If in doubt or if the fault comes back, call in a qualified professional. A question about a part? Write to us at info@instalpunt.nl.
Frequently asked questions
What does Buderus boiler fault code OF- mean?
Insufficient flow through the boiler. Max. temperature difference between flow and return > 15 K Temperature difference between flow and safety temperature sensor > 15 K.
How do I fix fault code OF- on a Buderus boiler?
First check the cause described above. Then restart the appliance using the reset button. If the message comes back, a part usually needs replacing or the fault needs to be repaired by a qualified professional.
Which parts do I need for Buderus fault code OF-?
That depends on the exact cause. In the Buderus parts overview at Instalpunt you will find the current price and stock for each part.
Can I fix fault code OF- myself?
You can reset the appliance and check things like the water pressure or settings yourself. Work on gas-carrying parts must be left to a certified gas engineer.
All Buderus boiler faults and codes at a glance →