b119 error code
ACV Prestige MCBA-5 b119 code – Minimum gas-pressure switch opened while burner was on
What does ACV Prestige MCBA-5 boiler range b119 mean?
ACV documents b119 for the Prestige MCBA-5 range as “Minimum gas-pressure switch opened while burner was on”. The code identifies a controller-detected condition and must be interpreted against the exact boiler model and installation.
The code identifies the condition detected by the product; it does not always identify the failed component on its own. Confirm the full code and exact model before ordering parts or attempting a reset.
The ACV Prestige MCBA-5 boiler range b119 error code indicates aCV documents b119 for the Prestige MCBA-5 range as “Minimum gas-pressure switch opened while burner was on”. The code identifies a controller-detected condition and must be interpreted against the exact boiler model and installation. This guide explains what the code means, the symptoms and likely causes, the checks that are safe to make, and when to stop and arrange an authorised repair.
Symptoms you may notice
The Prestige controller displays b119; burner, heating or hot-water operation may be interrupted or restricted until the condition clears.
Common causes
Likely causes are those documented by ACV for minimum gas-pressure switch opened while burner was on, including the related control, safety, combustion, electrical or circulation circuit.
Before you start troubleshooting
Use the display, rating label or product menu to confirm the exact model. Similar-looking codes can have different meanings across product generations and regions.
- Record the complete code before switching the equipment off.
- Check only user-accessible controls, filters and external connections described in the manual.
- Do not open gas, refrigerant, combustion or electrical compartments.
Troubleshooting steps
Check the gas-pressure switch and gas supply pressure.
Can you fix this error code yourself?
The safest next step depends on the exact model and the cause behind the code. External checks may help, but a returning fault needs professional diagnosis.
A successful reset is not proof that the underlying issue is fixed. If b119 reappears, note when it happens and give that information to the service engineer.
Reset instructions
Record the code first. Use only the MCBA reset procedure in the official manual and do not exceed the manufacturer's stated reset attempts.
Applicable products and models
Prestige MCBA-5 boiler rangePrestige Solo 24, 32, 50, 75 and 120; Prestige Excellence 24 and 32Legacy MCBA-5 generationWhen to contact a professional
Contact an ACV-qualified heating engineer when the code returns, a safety circuit is involved, or diagnosis requires internal access, measurements, programming or component replacement.
Frequently asked questions
What does ACV Prestige MCBA-5 boiler range b119 mean?
ACV documents b119 for the Prestige MCBA-5 range as “Minimum gas-pressure switch opened while burner was on”. The code identifies a controller-detected condition and must be interpreted against the exact boiler model and installation.
Can I fix ACV Prestige MCBA-5 boiler range b119 myself?
Some external checks may be suitable for the user, but the result depends on the exact model and cause. Use the official manual and arrange service if the code returns.
Should I reset the product after code b119?
Record the code first. Use only the MCBA reset procedure in the official manual and do not exceed the manufacturer's stated reset attempts.
When should I arrange a repair?
Contact an ACV-qualified heating engineer when the code returns, a safety circuit is involved, or diagnosis requires internal access, measurements, programming or component replacement.