There’s a valid and often misunderstood distinction between what’s written in guidance and how systems are delivered in practice.

Approved Documents such as Part L don’t typically declare specific products or actions as “mandatory.” Instead, they define performance, efficiency, and compliance expectations. In the UK heating market, those expectations are consistently met through:

• System cleaning
• Chemical protection
• Filtration
• Proper commissioning and documentation

That isn’t marketing language, it’s industry reality.

Installers don’t work in documents; they work in homes. And in real installations, skipping system preparation and protection introduces avoidable risks:

• Reduced system efficiency
• Increased likelihood of failure
• Compromised warranties
• Greater exposure to call‑backs and disputes

ADEY’s position is simple

ADEY’S Best practice exists to protect installers, not to complicate their work. While individual words in guidance can be debated, the outcomes cannot. Systems must be able to:

• Perform as designed
• Be commissioned and evidenced correctly
• Meet manufacturer expectations
• Remain reliable over time

Our role is to support installers in delivering systems that work, comply, and last.

That’s why ADEY continues to champion best practice: not as a theoretical ideal, but as the most reliable route to success on site.