Underfloor Heating Repair

One room that stays cold, a floor that never gets properly warm, or a system that has stopped altogether. We find the fault and fix it, anywhere inside the M25.

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Customer Satisfaction

Most underfloor heating faults come down to a handful of parts. A stuck actuator, a flow meter that has been knocked shut, a seized pump, a blending valve set too low, or air sitting in one of the loops. We work through the system in order, at the manifold and at the controls, so we find the fault rather than swapping parts at it.

Tell us which rooms are cold and what the thermostat is doing. That usually tells us what to bring before we set off. We cover London inside the M25, and the phone line is open 8am to 5pm, Monday to Friday.

eurocone fitting for manifold to underfloor heating pipe pert 2 1

Customer Reviews

Related services

We also handle heating repairs, central heating controls, boiler repair and power flush across London.

What is your system doing?

Underfloor heating fails in a handful of recognisable ways. Tell us which one sounds like yours and we will know roughly what we are looking for before we arrive. If you would rather try a few things first, our guide to underfloor heating not working covers the four checks that take five minutes.

One room stays cold

The rest of the floor works. Usually a stuck actuator, a closed flow meter or a blocked loop.

Warm, but never hot

The floor takes the chill off and no more. Often the blending valve or the flow temperature from the boiler.

Thermostat on, floor cold

The controls say the heating is running. Commonly the wiring centre, the pump or a failed floor sensor.

Radiators work, floor does not

The radiator circuit is fine and the underfloor circuit is dead. Normally the pump or the zone valve.

Stopped after a power cut or new boiler

Controls lose their settings and wiring gets reconnected wrongly. We reset and recommission the system.

Gurgling or banging pipes

Air in the loops. The system needs bleeding at the manifold and refilling to the right pressure.

Pressure keeps dropping

We check the expansion vessel, the pressure relief valve and the pipework and joints we can see.

Damp patch or suspected leak

We inspect visually to find where the water is coming from. If the leak cannot be seen, we will tell you and point you to a specialist detection contractor.

What we check

Diagnosis first, parts second. We work through the system in order so you are not paying for guesswork.

Manifold flow meters, balancing and loop temperatures
Actuators on each zone, including ones stuck closed
Blending valve and mixing valve settings
Circulating pump and zone valves
Wiring centre, thermostats and floor sensors
Air locks, system pressure and water quality
Boiler or heat source flow temperature feeding the manifold

Wet systems are our specialism

We work on wet underfloor heating, the type run in pipework from a manifold. That is where our experience is and it is all we take on.

Wet underfloor heating

Pipework run in screed and fed from a manifold. Faults are usually mechanical: pumps, actuators, valves, air, sludge or a leak.

Electric underfloor heating

We do not work on electric mats and cables. Those faults sit with an electrician rather than a heating engineer, so we would rather say so now than take a call out fee for a job we are not the right people for.

Flats on a heat network

A lot of London underfloor heating sits in new build flats fed by a Heat Interface Unit rather than a boiler. When the floor goes cold in one of those, the fault is often in the HIU or its controls, not in the underfloor system at all.

HIUs are one of our specialisms. We service and repair them across London, so we can check both sides of the system on the same visit instead of sending you to a second company.

What happens when we come out

We talk it through first

Call us and describe what the system is doing. That usually tells us what to bring.

We test before we touch anything

Manifold, controls, pump and heat source get checked in order, so we find the fault rather than swapping parts at it.

You hear the price before we start

We tell you what is wrong, what it takes to fix it and what that costs. Nothing goes ahead until you agree.

We fix it and show you it working

Where we can finish on the day, we do. Where a part has to come in, you get a date before we leave.

What it costs

£150

Call out fee, including VAT, payable in advance.

It covers the engineer arriving and up to one hour on site. If the job needs a fixed price quotation and you go ahead, the £150 comes off the final total. If we cannot give you a quotation, the fee is refunded in full.

We quote fixed prices and never charge by the hour. Where a part has to be ordered, you get the cost and a date before we leave.

Frequently Asked Questions

Why is one room cold when the rest of the floor is warm?

Each room is a separate loop at the manifold, controlled by its own actuator. The usual causes are an actuator that has stuck closed, a flow meter that has been turned down or shut off, air trapped in that one loop, or a thermostat in that room that is no longer calling for heat. All four are checked at the manifold, so this is normally a same visit fix.

My thermostat says the heating is on but the floor is cold. What now?

The thermostat is only asking for heat. Something further down the chain has to answer it. We check whether the wiring centre is passing the signal on, whether the pump is running, whether the actuators are opening and whether the boiler or HIU is sending hot water to the manifold at all. Before you call, it is worth checking the thermostat batteries, because a flat set is one of the most common causes.

The system keeps losing pressure. Is that a leak?

Often, but not always. Pressure also drops through a faulty expansion vessel, a leaking pressure relief valve or air being bled out repeatedly. We work through those first. If a leak is visible, we will quote to repair it. Where a leak is buried and cannot be seen, we do not carry out specialist non-invasive detection, and we will point you to an approved contractor through WIAPS.

The floor is warm but never gets hot. Is that a fault?

Not always. Underfloor heating runs at a much lower temperature than radiators, so a correctly set floor feels warm rather than hot. It is a fault when the room never reaches the temperature you set it to. The usual causes are a blending valve set too low, a boiler flow temperature that is too low for the manifold, loops that need balancing, or sludge slowing the circulation.

Do you work on electric underfloor heating?

No. We specialise in wet underfloor heating, the type run in pipework from a manifold. Electric mats and cables are an electrical fault rather than a plumbing one, so you need an electrician who works on floor heating. We would rather tell you that now than charge you a call out fee for a job we are not the right people for.

How soon can you come out?

Call 020 3764 2713 between 8am and 5pm, Monday to Friday, and we will give you the soonest slot we have. Describing the fault on the phone helps, because it tells us what parts to load before we set off.