Refrigerant balance — a practical guide to a balance that adds up

If there's one thing that routinely goes wrong at audits, it's the refrigerant balance. Not because installers are sloppy — but because it's administratively harder than it looks. A 13.6 kg R-32 cylinder that spends years travelling around in vans, ends up half-empty on a warehouse shelf, hands over a bit of gas to installation X, is then partly recovered, then decanted into another cylinder — it all has to add up to the exact decimal, or the balance doesn't close.

The six types of changes

In Koldwerk we distinguish six types of changes, mirrored on the F-gas Regulation:

1. PURCHASE — receiving a filled cylinder from a supplier. Goes ínto the cylinder stock. 2. ADDITION_TO_INSTALLATION — topping up an installation from a cylinder. Goes óut of the cylinder, ínto the installation charge. 3. RECOVERY — pumping refrigerant from an installation back into a (recovery) cylinder. Goes óut of the installation, ínto the cylinder. 4. TRANSFER — decanting refrigerant from cylinder A to cylinder B. Two mirrored entries: an outgoing one on A, an incoming one on B (Koldwerk creates the offsetting entry automatically). 5. DISPOSAL — refrigerant destroyed or handed over for recycling. Goes óut of the cylinder, nobody takes it over. 6. RETURN_TO_SUPPLIER — a cylinder (full or empty) goes back to the supplier. A stock correction.

The work-order-linking principle

Every change should be linked to either a work order or an internal action with an audit trail. Specifically: an ADDITIONTOINSTALLATION at a customer must reference a work order number; a PURCHASE from a supplier must reference a supplier invoice (or at least a PO number).

At Koldwerk this link is enforced: you can't save an ADDITION or RECOVERY without an installation ID. That sounds strict, but it prevents the classic "I don't remember where those 2 kg went" situation.

TRANSFER and the offsetting-entry mechanism

A TRANSFER is technically tricky: you're moving refrigerant from a source cylinder to a destination cylinder. Both stock levels change at the same time. In Koldwerk this happens within a single database transaction: either both entries succeed, or neither does.

The interface enforces at form level that the destination cylinder has the same refrigerant type as the source — no R-32 into an R-410A cylinder. And the source cylinder itself can't be chosen as the destination (preventive UX). Server-side validation checks this again.

What if the balance doesn't add up?

First step: look at the balance overview page per refrigerant type. It shows, per type: total purchased, total added, total recovered, total disposed of, theoretical stock, measured stock. The difference between theoretical and measured is your problem.

The three most common causes:

1. RECOVERY not recorded. The technician took refrigerant out of a unit but didn't register a change. Result: the cylinder is heavier than the system says. 2. A genuine leak. Real loss through a leaking installation. Should be reported via the incidents module. Under Regulation (EU) 2024/573 art. 4(5), an established leak must be repaired "without undue delay" — there is no fixed 150-gram or 14-day threshold; the repair must be checked by a certified person within 1 month of the repair, and that recheck may only take place at least 24 hours after the repair (art. 4(5)). 3. A new cylinder without a PURCHASE entry. An unregistered cylinder from the van suddenly appears in the system as "empty" (the default for new cylinders). Its filled state is then "lost".

Tip: do a monthly quick balance check — takes 5 minutes, prevents audit disasters. At Koldwerk we have a balance-check cron in the pipeline for this, so deviations show up automatically in a dashboard widget.

Measured cylinder weight versus book stock

One thing to watch: measured stock is the physical weighing of a cylinder. Book stock is what your system says. The two should match to the gram. In practice: after every monthly walk through your warehouse you can enter the measured values, and Koldwerk automatically looks for the smallest deviation pattern. If the difference consistently goes in the same direction, your scale may be miscalibrated; if it's random, there's probably a missing entry.

What does it look like at an audit?

A Kiwa or STEK auditor looks at, as a minimum:

• 12 months of change history per cylinder, with a full audit trail.
• A leak rate per type below 1% (STEK) and no unexplained shortfalls (BRL 100).
• RECOVERY as a percentage of ADDITION — a healthy ratio for maintenance companies is around 30-50%.
• Work-order-to-change cross-references: pulls 5 random changes, asks for the matching work order.

With Koldwerk you deliver this in one click via the reports module.

Further reading

• GWP values of refrigerants — the table that feeds your CO₂ equivalent calculation.
• F-gas leak checks: how often are they mandatory? — the frequencies per threshold, worked out.
• F-gas logbook: what needs to be in it? — installation record fields + retention period.
• R-32 vs R-410A vs R-454B — which synthetic refrigerant makes your balance future-proof?
• F-gas Regulation 2024/573 — the rules behind the balance.
• Am I subject to the logbook obligation? — check your situation in 10 seconds.

Disclaimer: this guide is an operational summary. For the exact regulations on F-gas administration, see Regulation (EU) 2024/573 and the Dutch Besluit activiteiten leefomgeving (Bal) with the Omgevingsregeling (opent in nieuw tabblad), which since 1 January 2024 replaced the Activiteitenbesluit/Activiteitenregeling milieubeheer under the Omgevingswet.