Buderus fault code B8L534
Fault code B8L534 on a Buderus boiler (including Logamax plus GB402-320 G20 and Logamax plus GB402-320 G25) means: No gas pressure or additional flue gas pressure limiter (pressure > 7.5 mbar) has tripped. Although solenoid valve 1 should be open, there is no gas pressure. The burner tries to start three times in succession, then waits for one hour, and then makes three start attempts again. Reset the appliance once. If the code comes back, a part is usually faulty.
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 B8L534 on a Buderus boiler indicates: No gas pressure or additional flue gas pressure limiter (pressure > 7.5 mbar) has tripped. Although solenoid valve 1 should be open, there is no gas pressure. The burner tries to start three times in succession, then waits for one hour, and then makes three start attempts again.
Fixing fault code B8L534: step by step
- Check that the gas valve at the appliance is open and that other gas appliances, such as the hob, are getting gas.
- Reset the appliance once. If the code comes straight back, do not keep resetting it.
- If the code comes back, the problem is the gas supply or the gas valve. Work on gas-carrying parts is for a qualified heating engineer.
- Smell gas? Close the gas valve, open windows and doors and call the gas emergency service straight away.
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 €12.95 (€16.95 for more distant countries), usually 3–5 working days.
This message does not point directly to one faulty part. If the code keeps coming back, view the Buderus parts:
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 B8L534 mean?
No gas pressure or additional flue gas pressure limiter (pressure > 7.5 mbar) has tripped. Although solenoid valve 1 should be open, there is no gas pressure. The burner tries to start three times in succession, then waits for one hour, and then makes three start attempts again.
How do I fix fault code B8L534 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 B8L534?
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 B8L534 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 →