This list is for facility managers and property owners across the North East who run commercial wet heating systems and need to find leaks before they become plant damage, downtime or a safety incident. The entries cover water, gas and concealed leaks, and each is marked by how disruptive it is, who should operate it and where it stops being useful. We chose them for suitability to commercial heating, not for novelty. Gas-related work is always left to Gas Safe registered engineers, whose registration you can check on the Gas Safe Register.
Commercial Boiler Solutions is a Gas Safe registered service, not a device. It provides commercial boiler maintenance, annual inspections, emergency callouts, gas repairs and component replacement for properties across the North East and Northumberland, including Newcastle, Sunderland, Middlesbrough, Tyneside, Wearside, Teesside and North Yorkshire. It holds a 5-star customer rating and offers same-day response.
Its distinctive strength on this list is that the same engineer who finds a leak on boiler plant or the gas supply can also repair it. Most other methods here locate a fault and then hand over to someone else. Where the question is gas, or whether a pressure drop comes from a pipe, a pressure relief valve or an expansion vessel, that combination of diagnosis and regulated repair saves time.
The service works alongside your site BMS and any existing maintenance contracts, so there is little setup beyond agreeing scope and access. Day-to-day running stays with your own team; the engineers attend on a schedule or when called. Sites with several buildings may find a regional maintenance contract easier to manage than ad hoc visits.
The limits are plain. It is not a continuous in-house monitoring system, and it does not carry out specialist buried-pipe surveys such as correlator or tracer gas work. If your problem is a leak under a slab or in a buried main, you will need a specialist survey contractor alongside. Pricing is quote-based and depends on the number and type of boilers, site access, contract frequency and whether the visit is planned or emergency.
Best for: Sites needing competent, regulated leak diagnosis and repair on boiler plant.
Pressure monitoring is the simplest way to find out whether a sealed system is losing water. A sealed system is a closed heating circuit held at pressure by an expansion vessel, topped up through a filling loop. A pressure decay test isolates the system or a zone, records the starting pressure and measures how far it falls over a set period.
It is the cheapest way to confirm that a leak exists, which is its main strength. No specialist kit is needed beyond working gauges and a disciplined log, so your own maintenance team can run it as an observation exercise. Recording pressure at the same time each day, alongside outside temperature and any top-ups, often shows a pattern within a week or two.
The weakness is interpretation. Falling pressure does not always mean a leaking pipe. A failed expansion vessel, a weeping pressure relief valve or a faulty filling loop can produce identical symptoms, and none involve a hole in the pipework. The method also never gives an exact location. Isolating valves, draining or any adjustment to boilers and controls should be left to a competent engineer, and gas work to a Gas Safe registered one.
Pricing is mostly staff time. Where a contractor carries out a test, cost depends on the size of the system, the number of zones and how long monitoring runs.
Best for: First-line check for any site noticing repeated top-ups.
Make-up water is the fresh water that enters a sealed system through the filling loop to replace losses. Fitting a meter on that line and linking it to your building management system turns a hidden problem into a measurable one.
Its distinctive value is continuous, out-of-hours warning. A leak that starts on Friday evening in an unoccupied building can run all weekend unnoticed. A metered filling loop with alarms flags unusual fill volumes or frequent fills as they happen, and low-pressure alarms can warn before the system locks out.
Integration is with your BMS, so this suits larger or multi-building estates that already have one. Installation involves plumbing work at the filling loop and BMS configuration, normally by your heating contractor and controls provider. Facilities staff then own the alarm settings and response procedure.
It detects loss, not location. Poorly tuned alarms either miss slow leaks or generate nuisance alerts that people learn to ignore, so thresholds need reviewing after the first few weeks. Without a BMS the cost and complexity may be hard to justify. Pricing is quote-based and depends on meter type, the number of systems, BMS work and any remote alerting service.
Best for: Larger or unoccupied-at-weekends estates with a BMS.
Thermal imaging uses an infrared camera to show surface temperature differences. On a heating system, a warm patch on a floor or a cool streak on a wall can indicate a concealed pipe, a leak or a failed section of underfloor heating.
Its distinctive strength is mapping heat patterns across large surfaces without opening anything up. A survey of a school corridor, retail floor or office suite can be done without lifting finishes, which keeps disruption low.
The key caution is that a thermal camera sees temperature, not water. Many people assume it shows leaks directly; it shows a thermal pattern that may be caused by a leak, but also by insulation gaps, draughts or sunlight. Findings need confirmation with another method, such as a moisture meter or pressure test. Surveys also work best with the heating running and a clear temperature difference between the pipes and the surroundings, so timing in the cold months can help.
Reporting software from the camera manufacturers is the usual integration. Most sites use a survey contractor, since interpretation takes experience. Pricing varies widely, from buying a camera to commissioning a survey, and is affected by camera specification, survey area and report depth; check current quotes as of 2026.
Best for: Surveying underfloor and concealed pipework.
Pressurised water escaping from a pipe makes a distinctive noise. Acoustic detection listens for it, and a correlator compares the sound arriving at two sensors on the pipe to calculate how far along the pipe the leak lies.
That distance calculation is what sets it apart, especially on buried metallic mains between plant rooms and buildings. On a campus, hospital site or industrial estate, it can turn a vague search across a car park into a targeted dig.
It performs poorly on plastic pipe, which carries sound badly, and in noisy environments such as busy plant rooms, roads or sites with running machinery. Surveys are often done at quiet times for that reason. Equipment is specialist, so it is normally delivered by a survey contractor rather than bought in. Your role is to supply pipe drawings, access to valves and a safe working area.
Pricing is quote-based and moves with site size, length of buried pipe, access difficulty and out-of-hours working. Any repair that follows on gas-fired plant or gas pipework must be done by a Gas Safe registered engineer.
Best for: Campus or industrial sites with buried heating mains.
Tracer gas testing is the method to consider when other approaches have not found the leak. A mix of hydrogen and nitrogen is introduced into drained pipework, and a sensitive surface detector picks up the tiny amounts that escape through the leak.
It is worth clearing up a common misunderstanding: the tracer is not natural gas. The commonly used mix is non-flammable, and it is separate from the gas supply that fuels your boilers. Contractors should confirm the exact mix and handling requirements for your site, and you should ask them to explain these before work begins.
The main drawback is downtime. The system has to be drained and isolated, so testing is a planned job, often timed outside the heating season or over a weekend. That is awkward for sites that cannot go without heat, such as care homes. Refilling, re-treating the water and recommissioning add to the programme.
It is delivered by specialist contractors, with little needed from your team beyond access and shutdown planning. Pricing is quote-based and depends on pipe length, drain-down and refill effort, access and the number of test zones. Verify current requirements and costs with your contractor as of 2026.
Best for: Hard-to-find leaks where thermal and acoustic methods fail.
These are the inexpensive confirmation tools. A moisture meter reads damp in walls, floors and ceilings, either by pins pushed into the surface or by a non-invasive sensor placed against it. A borescope is a small camera on a flexible probe that lets you look into voids, ducts and ceiling spaces through a small hole.
Their distinctive benefit is cost. They tell you cheaply whether a suspected spot is wet and let you look inside before committing to opening up finishes. They pair well with thermal imaging: the camera suggests a location, the meter and borescope check it.
The limits are significant. Readings are relative, not absolute, and vary with the material being tested. Damp can come from a roof leak, condensation, a drain or a heating pipe, and a meter cannot say which. Use the results as evidence to narrow the search, then confirm the source with pressure testing or another method.
Borescopes must never be used to inspect boilers, flues or gas pipework as a substitute for a competent engineer; that work belongs to a Gas Safe registered professional. Pricing ranges from budget handheld units to professional-grade equipment, depending on probe length, image quality and recording features.
Best for: Confirming suspected leak locations before opening up.
Fluorescent dye is added to the system water. After it has circulated, a UV torch is used to inspect joints, valves and pump seals, where any weep glows brightly. It suits small, slow leaks that leave little visible water.
That is what it does best compared with the other methods: it makes minor weeps visible in accessible plant rooms, where a slow drip may evaporate before anyone sees it. It is a cheap way to turn "somewhere around the pump set" into a specific joint.
It is of little use for leaks in inaccessible voids, under floors or in buried pipe, because you cannot shine a torch on them. Dye may also interact with water treatment, so check compatibility with your inhibitor and the system manufacturer's guidance before adding anything. Dosing should fit in with your water treatment programme, ideally agreed with whoever manages it.
Dosing and any work near boilers and gas-fired plant should be handled by a competent heating engineer, with gas work always done by a Gas Safe registered engineer. Pricing is low and depends on system volume and the product used; check current prices as of 2026.
Best for: Tracking minor weeps in plant rooms.
This is the only category here aimed at gas rather than water, and it carries different rules. Handheld combustible gas detectors, leak detection fluid and tightness testing equipment are used by Gas Safe registered engineers. Fixed detectors in plant rooms provide continuous monitoring and alarm.
If you suspect a gas leak, do not investigate it yourself. Leave the area, avoid switches and naked flames, and call the National Gas Emergency Service on 0800 111 999. Gas work must be carried out by a Gas Safe registered engineer, and the Gas Safe Register lets you verify any engineer. Duties under the Gas Safety (Installation and Use) Regulations 1998 and the Health and Safety at Work Act 1974 sit behind these requirements.
Fixed systems usually connect to boiler house safety interlocks and alarm panels, which can shut off the gas supply or sound a warning. Installation, commissioning and testing should be done by competent, Gas Safe registered professionals, with your facilities team responsible for responding to alarms through an agreed procedure.
The limitation is deliberate: this equipment must be operated and interpreted by Gas Safe registered engineers and is not for DIY use. Pricing depends on detector type, the number of sensors, panel integration and calibration or servicing intervals, so ask for a quote as of 2026.
Best for: Boiler houses with a gas supply requiring detection and safety compliance.
For routine monitoring, start with pressure logs and make-up water metering. They are low cost, and they tell you early whether water is being lost. Before assuming a pipe has failed, have the expansion vessel and pressure relief valve checked, since either can mimic a leak.
For concealed or buried pipework, combine methods: thermal imaging to suggest where, a moisture meter and borescope to confirm, then acoustic or tracer gas testing through a specialist contractor if the leak is still elusive. For out-of-hours sites, metering with BMS alerts gives the earliest warning.
For a suspected gas leak, none of the DIY-safe methods apply. Leave the area, call 0800 111 999, and let a Gas Safe registered engineer handle detection and repair. Commercial Boiler Solutions provides that service across the North East and Northumberland, alongside inspections, maintenance contracts and emergency callouts. Our FAQ answers common questions about booking and response.