The FHF-F Manifold is used for controlling water
flow in underfloor heating systems. Each pipe
in the floor heating system is connected to the
manifold, thus making it possible to control water
flow or heat supply to each room in the building
individually.
The manifold comprises of a supply and return
manifold. The supply manifold includes individual
shut-off of each circuit as well as an individual
flowmeter per circuit. The return manifold is
equipped with integrated Danfoss pre-setting
valves securing optimal hydraulic balance in the
system.
The valves can be controlled electronically by
thermal actuators or act as self-acting units by
means of remote temperature adjusters.
The manifold is supplied in modules of up to 12
outlets. Ball valves are available as an option for
positive shut-off between the manifold and the
system.
The end pieces FHF-EM and FHF-EA are supplied
with manual airvents or alternatively with automatic airvents.
The pre-setting of the manifold valves determines
the flow in the floor heating pipes and is therefore an important factor for obtaining optimal
hydraulic balance in the system. Correct hydraulic
balance is important if optimal comfort is to be
achieved with minimum energy consumption and
is easily carried out following the example shown
below.
Example
Room 1 1 Determine longest pipe/largest room 25 m
2 Desired cooling (ΔT)5 °C (typical)
3 Determine heat requirement for the room50 W/m
4 Conversion factor 1.16
5 Calculation of flow for the roomQ (l/h) = 50 W/m2 x 25 m2
The diagrams show the capacities for each heating circuit at different pre-settings of the manifold
valves. Based on the above calculations and capacity diagrams each manifold valve is pre-set by
Item DescriptionMaterial
1SightglassHeat resistant plastic
2Flowmeter nutBrass, CuZn39Pb3
3Flowmeter insertBrass, CuZn39Pb3
4Supply manifold bodyBrass, CuZn40Pb2
rotating the red ring until the correct value on the
ring is in-line with the sight mark on the valve.
Max differential pressure: 0.6 bar
Max working pressure: Manifold with flowmeter 6 bar
Max test pressure: Manifold with flowmeter 10 bar
Max flow temperature: 90 °C