Underfloor Heating Repair

The symptom points to where to look:

We check the system in order, from the heat source to the floor:

• Heat source: Whether the boiler or heat pump is producing heat and sending it to the underfloor circuit. Boiler faults are repaired through our boiler repair service, by Gas Safe registered engineers, as the law requires.
• Pump and mixing valve: The pump at the manifold circulates the water and the mixing (blending) valve lowers its temperature for the floor. A seized pump or a stuck valve leaves the whole floor cold, or too hot.
• Actuators: Each zone has a small electric actuator on the manifold that opens the loop when the thermostat calls for heat. They are a common failure, and most can be checked and replaced without draining the system.
• Flow meters: The gauges on the manifold show whether water is moving through each loop and let us balance the flow between rooms.
• Air locks: Air trapped in a loop stops it heating. We purge each loop through the manifold until the air is cleared.
• Thermostats and wiring centre: The thermostat must call for heat and the wiring centre must pass that signal to the actuator and pump. Room thermostat faults are also covered by our thermostat and control maintenance and repair service.

First, we confirm the leak is in the floor and not at the manifold, where most leaks are found. Each loop is isolated at the manifold and pressure-tested in turn, which shows which loop is losing pressure. Then we run warm water through that loop and use thermal imaging to follow the pipe and find the hot spot where water is escaping, along with other non-invasive methods from our leak detection and pipe repairs service. That means only a small area of floor is opened.

The damaged section is cut out and joined with a coupling made for underfloor heating pipe, then pressure-tested before the floor is reinstated. Many floor pipe leaks are caused by a nail, screw or drill during later work, so always check the pipe layout before fixing anything into a heated floor. If tiles were lifted, we relay them through our replacing cracked or chipped tiles service.

Electric underfloor heating has no water or moving parts, so faults are usually with the thermostat, the floor probe or the supply. We test the heating mat or cable for its resistance and insulation resistance and compare the readings with the manufacturer's figures. If the cable itself is broken, the break can be located with specialist equipment, a few tiles lifted, and the cable joined with a repair kit. Repairs to the supply or circuit are carried out through our electrical repair services and certified through one of the routes the building regulations allow.

A wet system benefits from a regular check, in the same way as a radiator system. An underfloor heating service covers:

• System pressure and the expansion vessel.
• Water quality: Inhibitor level, and the filter, as sludge can block narrow underfloor pipes.
• Flow rates in each loop, rebalanced where needed.
• Actuators, pump and mixing valve, checked for correct operation.
• Thermostats and settings, including schedules and flow temperature.

The boiler needs its own yearly check through our boiler servicing service. If your home has radiators too, our central heating system maintenance service can cover both at once. Electric underfloor heating needs little routine maintenance beyond checking the thermostat.