Description
78mm Core Bit for 22mm & 28mm Primary Pro DC78
Primary Pro Diamond Core Bit
Primary Pro Diamond Core Bits are designed to drill the correct hole size when installing insulated pipework through external walls during heat pump installations.
Using the correct core size ensures the hole is perfectly suited to fit Primary Pro Sleeves, allowing insulated pipework to pass through the wall while leaving the correct clearance for sealing.
Once the sleeve is installed, the pipe entry point can be sealed using Primary Pro Bond & Seal or finished with Primary Pro Sealing Rings, helping create a secure and weather-resistant seal.
The diamond cutting edge allows installers to drill cleanly through common wall materials such as brick, block and masonry, producing accurate openings for external heat pump pipe installations.
Key Features
• Designed for installing Primary Pro insulated pipework through walls
• Creates the correct hole size for Primary Pro Sleeves
• Diamond cutting edge suitable for brick, block and masonry
• Helps achieve a clean and accurate wall penetration
• Works alongside Primary Pro Sleeves, Bond & Seal and Sealing Rings
Available Sizes
78mm Diamond Core Bit – DC78
Used for installing the Primary Pro 22mm/28mm Sleeve




