Connecting an underfloor heating (UFH) manifold to a boiler requires several steps. Here’s a general overview of the process:

1. Determine the type of underfloor heating system you have and the requirements of the boiler. Make sure the boiler is compatible with the type of UFH system you have installed.
2. Install the manifold near the boiler, making sure it is securely mounted to the wall and level.
3. Connect the flow and return pipes from the boiler to the manifold. This is typically done using standard plumbing fittings like compression couplings or soldered fittings.
4. Connect the flow and return pipes from the manifold to the underfloor heating circuit(s). This is usually done using a series of valves, connectors, and pipe fittings.
5. Fill the UFH system with water and pressurize it to the required level.
6. Test the system for leaks and make any necessary adjustments to the flow and return temperatures.
7. Finally, commission the system by setting the correct flow and return temperatures on the boiler and adjusting the flow rates on the manifold to ensure even heat distribution throughout the UFH system.

It’s important to note that the specific steps and materials required will depend on the type of UFH system and boiler you have, as well as any local building codes and regulations. It’s recommended that you consult with a qualified heating engineer or plumber to ensure that the installation is done safely and correctly.