The Grant Aerona3 Installation Pack A typically refers to a complete set of installation materials and components designed for the Grant Aerona3 air source heat pump system. The Aerona3 is a type of heat pump produced by Grant UK, which is used for providing heating and hot water in residential and commercial settings.

The Installation Pack A would include everything needed for installing the Aerona3 heat pump, such as:

Aerona3 Installation Pack A - S-Plan Non Pre-Plumbed

• Combined Volumiser/Low Loss Header
• 7 Day Immersion Programmer (Legionella)
• Flexi Foot Kit
• Mag One DUO Filter
• 18L Sealed System Kit
• Wiring Centre c/w DHW Priority
• DHW Programmer
• 32A AC Isolator

It's important to note that such installation packs are typically designed for qualified installers to use, and it’s essential to follow all guidelines and regulations during installation to ensure safety and optimal performance.