CodeRegistry
Brands
  1. Home
  2. Buderus
  3. Logamax plus Boilers
  4. 7/l/
About·Privacy·Terms

CodeRegistry — Your global library for technical solutions.

For your safety: always follow the equipment manufacturer’s official manuals. CodeRegistry is an independent help site and is not affiliated with the brands listed here.

7/l/

Blocking fault 7/l/ (2/8/0) - UBA 3 control unit is defective

Buderus · Logamax plus Boilers

What does 7/l/ mean?

The boiler's UBA 3 control unit is identified as defective, leading to a complete shutdown of heating and domestic hot water. This is a blocking fault, requiring a manual reset.

Common Causes

  • Internal control unit failure
  • Electrical fault

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Press the 'Reset' button on the BC10 basic controller to clear the fault.

  2. 2

    Power cycle the boiler by switching it OFF and then ON via the main power switch.

  3. 3

    If the fault persists, contact a qualified service technician for diagnosis and potential replacement of the UBA 3.

Browse all codes in this manual (43)
Verified technical data. Last updated: April 2026

Related Faults

--/Flashing --/ - Communication fault between UBA 3 and BC10 controller0/y/Locking fault 0/y/ (2/8/5) - Return temperature sensor detected over 203°F (95°C)1/a/Blocking fault 1/a/ (3/1/6) - Flue gas sensor temperature too high
Source: Buderus Logamax plus Boilers
Open Manual (Page 48)Search more codes in this manual