Connecting a UFH manifold: Eurocone fittings, ball valves and pump packs

This guide is about the hardware at the wall: which parts go where, how a Eurocone joint is made, which pump pack to fit, and how to deal with tight cupboards and spare ports. To size the manifold first, see how many manifold ports do I need.

What connects to an underfloor heating manifold?

A wet UFH manifold has two bars, flow and return, with the heat source on one side and the loops on the other. Every part between them does one job: isolate, circulate, mix, or control a loop.

Our Dualmix manifold comes assembled with the pressure gauge and automatic air vent fitted. Our auto-balancing manifold has flow meters, air vents and fill and drain valves on both bars, and 1" BSP female main connections.

Which pump pack should I fit: blending or non-mixing?

Fit a blending valve pump pack when the heat source runs hotter than the floor needs, which is usual with a boiler. Fit a non-mixing pump set when the heat source already runs at floor temperature, as most heat pumps do.

Our blending valve is a thermostatic wax-capsule valve, so only the pump needs power. The packs come pre-assembled and bolt onto the manifold bars. For the detail behind the choice, see mixing and blending valves explained.

How do I mount the manifold?

Mount the manifold level on the wall, high enough for the pipes to rise from the floor in a smooth bend, and where you can reach it later. Fix it before you lay any pipe, so every loop starts and finishes at its final position.

1. Choose a spot as central as possible to the rooms it serves, such as a utility, cupboard or under the stairs.
2. Allow space at the side for the pump pack, and room below for the pipe bends.
3. Fix the brackets level, and check the bars are square to the wall.
4. Fit the 1" ball valve set and the pump pack before the loops, so you don't strain the pipe connections later.
5. If the pump pack has to sit on the next wall, use a 90° elbow connector set. It turns flow and return through a right angle with no extra pipework.

How do I connect UFH pipe to a Eurocone outlet?

Each loop end connects with a 3/4" Eurocone connector core: a nut, a split olive and a pipe insert. A good joint depends on a square cut, a clean pipe end and an insert pushed fully home.

1. Run the pipe up through a pipe support bend so it rises vertically to the outlet without kinking.
2. Mark the pipe at the height of the outlet and cut it square with a pipe cutter.
3. Ream or chamfer the inside edge, so the insert slides in without cutting the pipe.
4. Slide on the nut, then the split olive.
5. Push the insert into the pipe until it reaches its stop.
6. Offer the pipe to the outlet and tighten the nut with an open-ended spanner. Don't overtighten.
7. Label the loop at the manifold with the room and loop length.

Choose the core by the pipe's outside diameter and wall thickness, printed on the pipe. For example, 16 x 2.0mm pipe needs the 16 x 2.0 core. Our cores cover 8 sizes from 10 x 1.3mm to 20 x 2.0mm. You need 2 per loop: one on the flow bar and one on the return bar.

How do I connect the manifold to the boiler or heat pump?

Run the primary flow and return from the heat source to the pump pack's primary connections, with a pair of 3/4" isolating ball valves so you can service the pack without draining the system. The heating engineer sizes the primary pipe for the heat source and the floor's total output.

• Off a boiler: give the UFH its own zone. A 2-port motorised zone valve on the UFH primary flow lets the floor call for heat on its own. It comes in 22mm and 28mm.
• Off a heat pump: follow the heat pump maker's hydraulic layout. A PWM-ready pump such as the Grundfos UPM3 Flex lets the heat pump control pump speed.
• Flow and return: red handles mark flow and blue mark return on our ball valve sets. Check the pump pack's flow arrow before you fill.

Make the final connection to a boiler or heat pump through a qualified heating engineer.

Where do the actuators go, and how are they wired?

Fit one thermal actuator on each loop's valve on the manifold. Two loops in one room still need two actuators, both wired to the same thermostat zone.

• Our 2-wire 230V actuator matches 230V wiring centres such as the Heatmiser UH4 (4 zones) and UH8 (8 zones).
• Each zone on those wiring centres runs up to 6 actuators, within a 5A total board load.
• The wiring centre switches the pump and calls the heat source whenever any zone needs heat.
• The auto-balancing manifold's valves take M30 x 1.5 actuators, which our 2-wire actuators fit.

The wiring should be done by a qualified electrician.

What do I do with unused manifold ports?

Seal each unused outlet with a 3/4" female blanking cap. A spare loop has an outlet on both bars, so a spare loop needs 2 caps. Seal an open bar end with a 1" male blanking plug.

Spare ports are useful if you plan to add a room later. When you add the loop, unscrew the caps, fit 2 Eurocone cores and an actuator, and pressure test before the new loop is covered. If you need one more port on a Dualmix, a 1 port extension adds it. See pressure testing underfloor heating for the test.

Worked example: a 6 loop manifold off a boiler

Here is the connection kit for a 6 loop ground floor run from a system boiler, with a Dualmix manifold and a blending pump pack. Prices inc VAT, October 2026.

That is £551.68 before thermostats, the zone valve and the primary pipework. For a heat pump, swap the blending pack for a non-mixing set, such as the pre-assembled UPM3 Flex set at £207.

Products for this job

• Dualmix stainless steel manifold: 2 to 12 ports, from £54
• Auto-balancing stainless steel manifold: 2 to 12 ports, from £62
• Blending valve pump pack with Wilo 6m pump: £231
• Non-mixing pump set with Wilo 6m pump: £215
• Eurocone connector cores 3/4": from £1.42
• 90° elbow connector set 1": £26
• 3/4" ball valve set for blending valve: £19
• 2-wire thermal actuator 230V: £12

Browse manifolds and pumps, actuators and valves.

Frequently asked questions

What is a Eurocone fitting?

It is a standard 3/4" cone outlet used on UFH manifolds. You join the pipe with a Eurocone connector core, made up of a nut, split olive and insert sized to your pipe.

How many Eurocone fittings do I need?

Two per loop, one for the flow bar and one for the return. A 6 loop manifold needs 12.

Can I connect multilayer pipe to a Eurocone outlet?

Yes. Eurocone connector cores join both UFH pipe and multilayer pipe to 3/4" Eurocone outlets. Choose the core that matches the pipe size, such as 16 x 2.0mm.

Can I fit the pump pack at a right angle to the manifold?

Yes. A 1" 90° elbow connector set turns the flow and return through a right angle, so the pump pack can sit on the next wall.

Which side does the pump pack go on?

It depends on the pack. Our non-mixing set with the Wilo pump can be fitted left or right hand, with the primary from the side or bottom.

Do I need a blending valve with a heat pump?

Usually not. A heat pump designed for low flow temperatures normally uses a non-mixing pump set, so nothing holds back the flow temperature.

Can I add a loop to my manifold later?

Yes, if you have a capped spare port, or by adding a 1 port extension to a Dualmix. Then fit 2 cores and an actuator, and pressure test.

Sources: Danfoss guide: connecting composite pipes to an FHF manifold, IMI Hydronic UFH commissioning instructions