Pressure testing helps establish how a particular pipe circuit is behaving. It can be used for a water supply, central-heating system or underfloor-heating loop where the source of water loss is unclear. By isolating an appropriate section and observing it under suitable conditions, we can focus the leak detection investigation on the right area.
How pressure testing works
The relevant circuit is isolated where practical, then assessed using pressure testing equipment. The reading is considered with valve positions, temperature changes, system volume and the pipework layout. A pressure change can indicate that further investigation is needed, but it does not independently reveal an exact break point.
- 1
Identify what is being tested
We review the circuits, valves, appliances and any previous work so the test has a clear purpose.
- 2
Isolate and observe
An appropriate section is assessed under conditions suitable for its pipework and components.
- 3
Use the result
Findings help direct tracing to the relevant circuit and support checks after the plumbing repair.
When this equipment can help
- Repeated central-heating pressure loss and suspected concealed pipe leaks
- Separating several possible heating or water circuits
- Underfloor-heating manifold and loop investigations
- Post-repair checks after a plumbing repair
EXAMPLE INVESTIGATION
Several underfloor heating loops, one suspected leak
Where the manifold arrangement permits, testing individual loops can help distinguish an affected circuit from the rest of the system. That information focuses subsequent tracing. It does not show the exact point beneath the floor, so thermal imaging, tracer gas or another appropriate check may still be needed.
Building the evidence with other methods
Testing answers a system-level question: which part needs more investigation? Tracing methods help answer the next question: where is the loss? Bringing both stages together helps explain why a particular opening and repair have been proposed.
Pressure testing identifies a pattern of loss, not a precise leak location. A valve, appliance component or another system fault can also influence results. We use the test to guide the next appropriate method, such as thermal imaging, acoustic listening or tracer gas.
Compare leak detection methodsPreparing for an investigation
Make stop valves, plant cupboards and manifolds accessible where safe. Tell us if isolating the relevant circuit could affect another occupier, business equipment or a shared supply.
Tell us the property postcode, when the symptoms started and what has already been checked. Useful details include changes in water bills, boiler pressure, the location of damp patches and any recent building work.
Contact us about your hidden leak
We investigate and repair residential pipe leaks from our Windsor SL4 base, with appointments across the surrounding service area. Homeowners and residential landlords can enquire about the £1,195 package; commercial premises receive an individual quote.
Discuss your leak with usGOOD TO KNOW
Your pressure testing questions
Can a pressure drop have another cause?
Yes. Temperature changes, valve behaviour and system components can influence the reading. Repeated boiler pressure loss should be assessed in the context of the full heating system.
Should I pressure-test my own pipework?
Arrange the assessment with a suitable professional. The method and conditions must suit the installation; do not add pressure or isolate unfamiliar components based on a general website guide.
Do you also repair the leak?
Yes. We combine investigation, access and the plumbing repair in one residential package. We explain the proposed access before work begins and test the repair afterwards.
How does the £100 deposit work?
First, contact us about the leak. Once the job and appointment are confirmed, we send you a payment link for a £100 booking deposit. This is deducted from £1,195, leaving £1,095. Sending an enquiry does not take a payment or confirm an appointment.
Further technical reading
Vaillant: understanding boiler pressure loss. Manufacturer guidance explains the technology; the equipment selected for your visit depends on the investigation.