ATAG fault code BL 85
Fault code BL 85 on an ATAG boiler (including 24/32Ci and 24C) means: The controller has detected no water flow. Automatic air purge cycle is started. If water flow is detected during this cycle, the air purge cycle is ended and the burner is enabled. 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 BL 85 on an ATAG boiler indicates: The controller has detected no water flow. Automatic air purge cycle is started. If water flow is detected during this cycle, the air purge cycle is ended and the burner is enabled.
Fixing fault code BL 85: step by step
- Read the water pressure on the display or gauge. With the system cold it should be between 1.5 and 2 bar.
- If it is lower, top up to 1.5–2 bar with the filling valve or filling loop, then close the valve again.
- Bleed the radiators with a radiator key, then check the pressure again and top up if needed.
- Reset the appliance once. If the code comes straight back, do not keep resetting it.
- Does the pressure drop again within a few days, or does the code come back? Then there is a leak somewhere (radiator, pipe, pressure relief valve or expansion vessel) or the pressure or flow sensor is faulty.
Applies to
ATAG 24/32Ci, 24C, 24Ci, 35Ci, 35S, Enigma, Q-Solar, Q25C, 24/32Ci / FGO … autom: MCBA1415, 24C / FGO … autom: MCBA1415, 24Ci / FGO … autom: MCBA1415, 35Ci / FGO … autom: MCBA1415, 35S / FGO … autom: MCBA1415, E22C / FGO … autom: MCBA5417, E26C / FGO … autom: MCBA5417, E32C / FGO … autom: MCBA5417.
Click a model for the parts list and exploded view of that appliance.
Fault code BL 85 on other ATAG series
The same code does not mean the same thing on every series. Check the rating plate to see which series you have:
- BL 85 on Blauwe Engel, Enigma, Q-series, CMA 350, CMA 352, CMA 652: The controller has detected no water flow Automatic venting cycle is started. If water flow is detected during this cycle, the venting cycle is ended and the burner is enabled.
- BL 85 on Blauwe Engel, CMA 650: The controller has detected no water flow.
- BL 85 on Blauwe Engel II, SHR24 / FGO … autom: MCBA1415, SHR24 T(i) / FGO … autom: MCBA1415, SHR35 / FGO … autom: MCBA1415, SHR35 T(i) / FGO … autom: MCBA1415, SHR51 / FGO … autom: MCBA1415: The controller has detected no water flow. Automatic air purge cycle is started.
Matching parts
ATAG parts are available from Instalpunt; shipping to EU countries from €12.95 (€16.95 for more distant countries), usually 3–5 working days.
Parts per Atag-series: A Series · i Series (iCon) · Q Series · E Series · P-series (iCon) · Blauwe Engel · XL-series.
For fault code BL 85, the part involved is usually in the category: burner.
This message does not point directly to one faulty part. These are the parts that most often fit this appliance:
Atag pump gasket 3/4" DN20 R38x25x2 mm 2 pcs € 20.47
Atag sealing cap exhaust pipe Ø13mm for flue gas measurement € 22.58
Atag sealing ring intake fan SHR for OSS1/2/3/4 € 22.58
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 ATAG boiler fault code BL 85 mean?
The controller has detected no water flow. Automatic air purge cycle is started. If water flow is detected during this cycle, the air purge cycle is ended and the burner is enabled.
How do I fix fault code BL 85 on an ATAG 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 ATAG fault code BL 85?
That depends on the exact cause. In the ATAG parts overview at Instalpunt you will find the current price and stock for each part.
Can I fix fault code BL 85 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 ATAG boiler faults and codes at a glance →