Commissioning Underfloor Heating Manifold – Commercial Gas Engineers

These are the essential tools required to correctly commission an underfloor heating manifold.

It is essential to remove all air from the pipework or the floor heating pump will not circulate water through the Fastflo® tube. This could take up to 2 hours. It must be flushed and pressure tested prior to laying the floor deck.

1  Close the isolating ball valves that are connected directly to the blending valve.

2  Open the flow adjuster fully.

3  supply (top) manifold by lifting the
red collar and undo the black locking
nut and turn the red adjustment key
Remove the blanking cap from
the filling valve on the flow (upper) manifold. Fit the connection nozzle and connect a suitable hose from the mains water supply. Open the filling valve using the key.

4  Similarly fix a suitable hose to the drain valve on the return (lower) manifold.

5  Fully loosen or remove the blue protection cap from on the return (bottom) manifold.

6  Open the tap on the mains water supply and open the drain valve on the return (lower) manifold using the key on the blanking cap.
fully anti-clockwise tighten the
black locking nut replace the red
collar. blanking cap.

7  Run the water until all air is expelled from the pipe.

If the outflow is run into a bucket then air bubbles will be detectable.

once the air bubbles have been released. We would pump up the pressure to 4 bar and then leave for 24 hours. After that anything more than a 0.5 bar drop will mean that the purging process must start again as there is still air in the system.