Water underfloor heating repair starts with the question of where the fault is: in the floor pipes, the manifold, the pump unit or the controls. Pipes in concrete are rarely damaged, and most problems are in the manifold cabinet, where they can be fixed without opening the floor. The repair costs from €50 per call-out (diagnosis, bleeding, adjustment). Electric underfloor heating is an electrician's job, and we do not repair it.
First we look at how widespread the problem is. If one room or one part of the floor is cold, the fault is usually in that particular loop: air, a closed actuator or a clogged flow meter. If the whole floor is cold, the pump, the mixing unit and whether heat is arriving from the boiler or heat pump at all have to be checked.
The manifold distributes warm water to the floor loops. The flow bar usually has flow meters with a clear window that shows how much water goes through each loop. Over time the window clouds up and the float sticks, and then a loop may be closed even though the meter shows something else. The meter is cleaned or replaced.
The return bar has actuators that open and close a loop on a signal from the room thermostat. A faulty actuator often stays in the closed position, and the room stays cold. It is replaced without draining the system, because it sits on the outside of the valve.
If the manifold itself, its valves or joints are dripping, the manifold shut-off valves are closed and the seals or the damaged part are replaced. An old manifold with many leaks sometimes has to be replaced altogether.
Bleeding underfloor heating is not the same as bleeding a radiator. Air is driven out of the long pipes by flushing the loops one at a time with a flow of water through the manifold until the water runs without bubbles. After that the system pressure is checked.
Balancing means setting the flow for each loop according to its length. If it is not done, the short loops get most of the water while the long ones stay cool. The sign is a floor that is warm near the manifold but not in the far corner of the room.
Flushing is needed if the flow is weak in all loops and the meters cloud up quickly. The loops are flushed one at a time so that the sediment leaves the system rather than moving into the next loop. If there is sludge in the whole heating system, see heating system flushing.
The mixing unit mixes hot water from the boiler with return water so that the floor gets water at a temperature suitable for it, and the pump drives it through the loops. If the flow pipe at the manifold is cold, or the pump is silent or humming, the fault is usually in this unit.
The circulation pump, the three-way or mixing valve and its thermostatic head or actuator can be replaced. We do not service boilers or heat pumps: if heat is not arriving from the heat source, that is a separate service.
Description
In the form, say which rooms are cold, since when, and what the heat source is. A photo of the manifold will be useful when we get in touch.
Diagnosis
We check the pressure, the flow in each loop, the actuators, the pump and the flow temperature.
Repair
The faulty part is replaced or cleaned: flow meter, actuator, valve, seal or pump.
Bleeding and adjustment
The air is flushed out loop by loop, the flows are set and we check that all rooms start to warm up.
If the system pressure keeps dropping but there is no leak at the manifold, a loop in the floor may be leaking. Then each loop is tested separately with the others closed. The exact spot in the concrete is found with leak detection, and the floor is opened only there. For this see water leak repair.
Underfloor heating repair costs from €50 per call-out, which includes diagnosis, bleeding and adjustment. The price depends on whether bleeding and adjustment are enough or parts need replacing, and how many actuators have to be replaced. It also depends on whether the flow meters or manifold valves, the pump, the mixing unit or the three-way valve need replacing, and whether the thermostats and controls have to be checked.
The price does not include parts (actuators, meters, pump, valves), opening and restoring the floor if the leak is in the concrete, boiler or heat pump servicing, or electrician's work on the controls.
If you want floor heating in a new room or the old system has to be rebuilt, see water underfloor heating installation, from €300. If the radiators in the house are not heating well either, see radiator repair. All jobs are on the plumbing services page.
| Service | Price | Notes |
|---|---|---|
| Underfloor heating repair | from €50 | per call-out: diagnosis, bleeding, adjustment; parts extra |
| Water underfloor heating installation | from €300 | new system |
After submitting, we'll call you within 5 minutes!
We'll call you within 5 minutes!