GEL: Inhibited Chemical Descaling Liquids for Heating Systems

Professional Descaling: The 3-Phase Cycle

Problem: Using any acid to clean a coil can ruin it. The acid eats away at the limescale, but then continues to attack the copper and steel, leaving the system vulnerable to future corrosion.

Solution: GEL descaling products (e.g. GELCLEAN) contain an *inhibitor* that creates a protective film on bare metals, ensuring that the acid acts only on the limescale and not on the pipes.
For a job done right, follow the complete cycle:

1. **DESCULATION:** Circulate the inhibited acid via a wash pump (Europump).
2. **NEUTRALIZATION:** Discharge the acid and circulate a basic product (GEL Neutralizer) to bring the pH back to 7.
3. **PROTECTION:** Insert an anti-corrosion film (GEL Inhibitor) for long-term maintenance.

Exchanger Flushing vs. System Flushing

If you only need to clean the exchanger (scale), use acid (with the Europump pump).
If you need to clean radiators (oxide sludge), use non-acidic sanitizing products (SANITARY GEL) to avoid damaging the seals.

Frequently Asked Questions about Gel Descaling

1. Can I use these acids on aluminum pipes?

Yes, but only those products specifically labeled "Safe for Aluminum" and only if they contain an inhibited acid. Aluminum (often used in radiators) is very sensitive to acids, so descaling must be done quickly and followed by immediate neutralization to prevent corrosion.

2. Do I have to drain the entire heating system before descaling the exchanger?

No. To clean the boiler exchanger, the professional hydraulically disconnects it from the rest of the heating system. This allows the acid to circulate in a "small, closed" circuit (exchanger only), preventing the acid from entering the other radiators, which may be old and delicate.

3. Does the descaler also remove black sludge from radiators?

Acids are designed to dissolve **limestone**. Black sludge is **iron oxides (magnetite)**. Acid has little effect on it. For black sludge, you should use a specific **Remediation** product (not acidic), and then have it collected by a **Magnetic Sludge Remover**.