— blog
When your boiler starts to leak, it’s a clear sign that something isn’t right. Whether you notice a steady drip, a small puddle beneath the unit, or a sudden loss of pressure, a leaky boiler can quickly lead to bigger problems if ignored. Water can damage electrical components, corrode pipework, and reduce system efficiency, so it’s important to act fast. Understanding the causes, the immediate steps to take, and when to call a professional will help you handle the issue safely and effectively.
A leaking boiler is one of the most common issues homeowners face, particularly in older systems or those that haven’t been serviced recently. While a small leak may seem harmless, it often indicates an underlying mechanical fault that needs attention from a qualified heating engineer.
Several factors can lead to boiler leaks, and knowing what might be behind yours helps ensure it’s repaired correctly.
Corrosion and Wear: Over time, the metal inside your boiler can corrode, especially if there are untreated water impurities or a lack of inhibitor fluid. Corrosion can cause tiny holes to form in pipes or heat exchangers, allowing water to escape.
Faulty Pressure Relief Valve: Boilers have built-in safety mechanisms to release pressure when needed, but if the valve fails or pressure becomes too high, water can begin leaking from this point.
Damaged Seals and Gaskets: Constant heating and cooling can cause seals to expand and contract, leading to wear and eventual leaks.
Loose Pipe Connections: Vibration during operation may gradually loosen pipe fittings or joints, particularly after recent maintenance or installation work.
Cracked Heat Exchanger: A rare but serious issue, a cracked heat exchanger can cause internal leaks that reduce system performance and efficiency.
When you first spot a leak, it’s important to respond calmly and safely. Acting quickly can prevent further damage and keep your home safe.
Turn Off the Water Supply: Locate your stop tap, usually under the kitchen sink, and turn it clockwise to shut off the flow of water to your boiler.
Switch Off the Boiler and Power Supply: Isolate your boiler at the main switch to prevent electrical hazards.
Check the Pressure Gauge: If the pressure is too high (above 2.5 bar), this may be the cause of the leak. Don’t attempt to adjust it yourself, just note the reading for your engineer.
Contain the Leak: Place a towel or container under the leak to prevent water damage to flooring or skirting boards.
Call a Gas Safe Engineer: Avoid any DIY repairs. Only a qualified professional can safely inspect, diagnose, and repair a leaking boiler.
A leaky boiler can be caused by anything from a minor seal issue to a failing heat exchanger and without the right tools and experience, it’s impossible to tell. Professional engineers use diagnostic equipment to identify the exact cause and carry out safe, lasting repairs.
At Heatfire Ltd, our engineers specialise in boiler repairs in Walsall, Wolverhampton and Cannock. We understand how disruptive heating problems can be, which is why we aim to repair faults quickly, cleanly, and with minimal disruption to your home.
Regular maintenance is key to preventing leaks and ensuring long-term efficiency. By keeping up with annual boiler servicing, you can avoid the most common causes of water leaks. During a service, an engineer will:
Check and clean the heat exchanger, valves, and seals
Inspect for signs of corrosion or rust
Verify that the pressure is correctly balanced
Ensure that all pipe joints are secure
Refill the system with inhibitor fluid to protect against future corrosion
Simple steps like bleeding your radiators, keeping your boiler pressure within the recommended range, and booking an annual service can extend your boiler’s lifespan and save you from expensive repairs.
In some cases, especially if your boiler is more than 10–15 years old, a persistent leak may be a sign that it’s time for a replacement. Repairing a corroded or cracked heat exchanger, for example, can often cost more than installing a new boiler. A professional engineer can provide honest advice on whether a repair or replacement is the most cost-effective option for your situation.
If you’ve spotted a leak from your boiler, don’t wait for the problem to worsen. Heatfire Ltd offers professional boiler repairs in Walsall, Wolverhampton and Cannock, carried out by experienced Gas Safe engineers. We provide quick response times, transparent pricing, and high-quality repairs that restore your heating system’s safety and performance. Call our team today or complete our contact form to book your repair visit.
