F-Register
Leakage loss calculation
Explanation of relative leakage loss: leak top-ups divided by the nominal refrigerant charge.
Relative leakage loss helps assess how much refrigerant an installation has lost during a calendar year. It is a practical metric for maintenance, audit and root-cause analysis.
In F-Register, leakage loss is linked to the installation so deviations do not disappear in separate work orders or spreadsheets.
Relative leakage loss formula
L = B / N × 100%
Where:
| Symbol | Meaning |
|---|---|
| L | Relative leakage loss in percent. |
| B | Sum of all top-ups due to leakage during the calendar year, in kg. |
| N | Nominal refrigerant charge of the installation, in kg. |
Example
An installation has a nominal charge of 4.0 kg. During the same calendar year, 0.3 kg refrigerant is topped up due to leakage.
0.3 / 4.0 × 100 = 7.5%
The relative leakage loss is 7.5%.
Important difference: leakage top-up or extension
Not every top-up is treated the same way.
| Situation | Counts as leakage loss? |
|---|---|
| Top-up due to leakage | Yes |
| New installation | No, this belongs to the installation charge. |
| Installation extension | No, this increases the correct nominal charge. |
| Retrofit | Depends on registration and situation. |
| Maintenance without leakage | Not as leakage loss unless explicitly topped up because of leakage. |
That is why the reason for a top-up must be clearly recorded.
When is root-cause analysis needed?
If an installation loses an unusual amount of refrigerant, you need to explain why. Possible causes include:
- leakage at flare connection or coupling;
- leakage in evaporator or condenser;
- installation damage or vibration;
- incorrect previous charge;
- several small leaks during the year.
F-Register can show installations with increased leakage loss in audit reports so they can be checked specifically.
How F-Register records this
The action and reason are recorded on the work order. Only top-ups registered as leakage are included in leakage loss. The nominal charge remains unchanged because the system is filled back to its correct content.
This keeps the difference between normal installation charge, extension and leakage loss clear in the administration.