Creating and maintaining a STEK file
Anyone in the Netherlands who works on the refrigerant circuit of a refrigeration, air-conditioning or heat pump installation does so through a STEK-certified company with qualified technicians, and records every leak check in that installation's logbook. Appfront builds the software in which that logbook is filled in at the moment the work is done, with the refrigerant balance following automatically from it.
What the F-gas rules and STEK require of you
Since 11 March 2024, the new F-gas Regulation (EU) 2024/573 has applied in all member states. It tightens the rules on leak checks and repairs, on the use and prohibition of certain refrigerants, and encourages alternatives with a lower climate impact. For your company this has two consequences: what you may do to an installation and with which refrigerant, and what you must record about it.
In the Netherlands, this is implemented through STEK. Anyone who installs, charges, maintains or decommissions the refrigerant circuit must do so through a STEK-certified company and have the work carried out by a technician holding the relevant F-gas certificate. Your certification is reviewed every year, and that review checks whether your records are correct: which technician carried out which task, on which installation, with which refrigerant and in what quantity.
The bottleneck is almost never technical expertise but administration. A technician fills in a form on site, the slip goes back to the office and someone retypes it into the logbook. The refrigerant balance, which has to add up between what was purchased, topped up and recovered, then drifts out of line unnoticed. It shows up at the audit, and by then it is hard to reconstruct because the work was done months ago.
How we build your STEK software
We start with the technician's work on site. If that recording is short and complete, the logbook is correct and the balance follows automatically.
Which installations you manage, with which refrigerant, which charge and which check frequency. That frequency depends on the amount of refrigerant expressed in CO2 equivalent and on whether a leak detection system is present; we take those rules from the regulation rather than inventing them.
Every task on the circuit is given a type, a technician with their certificate, an installation and the associated quantity of refrigerant. Certificates have an expiry date; we build the monitoring of that in from the start.
We work in sprints and start with the on-site recording, because that is where the volume and the biggest time savings are. Your technicians help shape it and try an interim version early on in a real plant room.
We reconcile the refrigerant balance with purchasing and the cylinders, and before handover we run through the records using the questions asked in the annual review. Then we hand over to your back office.
What the software actually does
Six components that together make up the records. Which ones you need depends on how many installations you manage and whether you also purchase refrigerant yourself.
Logbook per installation
Every action on an installation in one place: leak-tightness checks, refilling, recovery, maintenance and repairs, with date, engineer and quantity. That log belongs to the installation and moves with it if management passes to another party.
Scanning at the installation
A code on the installation opens the right log and shows the charge, the refrigerant and the previous check. In a plant room with eight near-identical units, that prevents the most common error: recording under the wrong installation.
Engineers and their certificates
For each engineer, which F-gas certificate they hold and until when. Only someone who is authorised can record an action on the circuit, and the system warns well before a certificate expires so recertification can be planned.
A refrigerant balance that adds up
What was purchased, what is in cylinders, what was topped up and what was recovered or disposed of. The balance is updated continuously instead of being reconstructed at year end, so a discrepancy stands out while it can still be explained.
Check frequency per installation
The frequency of the leak-tightness check follows from the amount of refrigerant in CO2 equivalent and whether a leak detection system is present. The system calculates this per installation and plans ahead.
Leaks and repairs
If a leak is found, a fixed process starts: repair, followed by a re-check within the set deadline. It stays open until it has been carried out, because that second check is exactly the one that gets forgotten in practice.
Who we build for
Four types of organisation. The difference lies in whether you manage for third parties or for yourself, and in the size of the refrigerant inventory.
Refrigeration companies
The core group. Your certification depends on the quality of the file and your margin on how much time an engineer spends on admin. Often combined with a job sheet app, because the action and the job sheet belong together.
Retail, foodservice and logistics
Many refrigeration installations across multiple sites, often managed by an external party. Your question is demonstrability and oversight: where is a check still open, and does the balance add up per location.
Healthcare, data centres and industry
Climate installations where failure has immediate consequences, with an in-house technical department. Here STEK runs alongside regular maintenance, and a single schedule makes more sense than two.
Property and facilities management
You manage buildings with climate installations and contract out the refrigeration work. It then comes down to requesting and monitoring someone else's file, alongside your own facilities processes.
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What we use follows from how you work. Plant rooms, basements and roofs rarely have coverage, so working offline is a requirement. What we don't do is submit the registration on your behalf; the file is yours and stays with you.
Why Appfront
Recording at the installation
Every step between the action and the log is a place where something gets lost or ends up under the wrong unit. We build it so that recording on the spot is faster than filling in a job sheet.
The balance is the audit test
During the assessment, they check whether purchases, charges and disposals reconcile. By updating that balance continuously, you spot a discrepancy while it can still be explained.
Authorisation upfront, not afterwards
An engineer without a valid certificate should not be able to record the action. That is a check at the point of entry, not a finding in a monthly report.
Alongside what already runs
Your planning, invoicing and stock systems stay as they are. We build the layer in between through integrations, so an action never has to be entered in two places.
Security and privacy
The file contains personal data about your technicians: name, qualification and which actions they carried out and when. This is needed to demonstrate that a certified person did the work, and it also touches on their professional competence. We use that record only for this purpose and focus reporting on the installation and the balance, not on output figures per technician.
You also work with data about your clients' installations, including leaks and outstanding defects. That is information that should never leak to other clients. Access is therefore set up per client, with a portal that shows only their own installations. A recorded action cannot be changed silently: a correction is visible as a correction and does not overwrite the original, because a log that can be altered unnoticed after the fact is worthless at inspection. How we handle security ourselves is set out in our information security policy; reports from outside go through our coordinated vulnerability disclosure policy.
Frequently asked questions about the STEK file
Regulation (EU) 2024/573 has applied in all member states since 11 March 2024. It tightens the rules on leak checks and leak repairs, and on the use and phase-out of certain refrigerants, and it encourages alternatives with a lower climate impact. For your records, this mainly means that what you log must match what you actually do more closely. Exactly what applies to your installations depends on the refrigerant and the charge; we go through that per installation type during the discovery phase.
The frequency follows from the amount of refrigerant in the installation, expressed in CO2 equivalent, and from whether a leak detection system is present. More refrigerant means more frequent checks; a leak detection system can reduce the frequency. Because this is a calculation per installation rather than a fixed interval, we have the system work it out instead of setting it manually per client.
A technician holding the relevant F-gas qualification, working for a STEK-certified company. Both are required: the qualification belongs to the person, the certification to the company. We build that authorisation in as a check at the point of entry, so an action cannot be recorded by someone without a valid qualification. That is far better than discovering it afterwards at inspection.
It is the reconciliation between what you have purchased, what is in your cylinders, what has been topped up in installations and what has been recovered or removed. At the annual inspection this is calculated in full. If the balance is off, the question is where the refrigerant went, and that is hard to answer months later. By keeping the balance updated continuously, a discrepancy stands out while the technician still remembers the job.
Yes, and for this kind of work that is a requirement. Machine rooms, cold stores, basements and roofs have poor coverage, and that is exactly where the installations are. The app stores data locally and syncs as soon as there is a connection, showing clearly which actions have not yet been sent. What we explicitly design for is what happens when two technicians have worked on the same installation offline.
In that case you fix it, and then carry out a follow-up inspection within the set deadline to confirm the repair was effective. In practice, that second check is the part that most often gets left, because the urgency disappears once the repair is done. So we build it as a task that stays open and grows more urgent until it has been completed, with the outcome recorded in the same logbook.
Yes, and it saves your back office a lot of questions. Each client gets a portal showing their own installations, with the inspections carried out, the open items and the next deadline. For managers with multiple sites, it is the most requested feature. If management passes to another party, the logbook goes with it; it belongs to the installation, not to you.
That depends on the number of installations, whether you purchase refrigerant yourself and which integrations you want with work orders, invoicing and stock. On-site recording is usually quick to put to use and delivers the most value. Making the refrigerant balance reconcile with your purchasing takes more work, because it involves your stock administration. We give a well-founded estimate after the discovery phase.
Ready to build a STEK file?
Tell us how many installations you manage and how the logbook is kept at the moment, and we will help you think through on-site recording, the refrigerant balance and the monitoring of certificates and deadlines. We build this as a standalone application and as part of a broader project involving custom software or an app.