No Hot Water? What Your Boiler Might Be Telling You January 30, 2026 When you turn on the tap and find there’s no hot water, it can cause instant frustration, especially if you rely on your boiler for both heating and water supply. While the problem might seem sudden, it’s often your boiler’s way of warning that something isn’t quite right. Understanding what your system is trying to tell you can help you act quickly, avoid further damage, and restore comfort to your home. Common Reasons Your Boiler Has Stopped Producing Hot Water When your boiler stops providing hot water, it’s usually down to one of several common issues. Some can be fixed easily, while others need professional attention from a Gas Safe engineer. Thermostat or Timer Faults If your thermostat is set incorrectly or the timer has reset after a power cut, your boiler may not know when to heat the water. Double-check your settings to ensure the temperature and timing are correct. In some cases, an outdated or faulty thermostat can send inaccurate readings to the boiler, preventing it from firing up when needed. Low Boiler Pressure Low water pressure is a frequent cause of lost hot water. You can check this on the pressure gauge, anything below one bar can prevent your boiler from operating properly. While repressurising the system is sometimes safe for homeowners, it’s best to get expert help if you’re unsure, or if the pressure continues to drop over time. Ongoing pressure loss could point to a leak within the system that needs professional attention. Frozen Condensate Pipe During colder months, a frozen condensate pipe is one of the most common reasons for boiler shutdowns. The pipe carries waste water away from the boiler, and if it freezes, it creates a blockage that causes the boiler to lock out for safety. This can usually be fixed by gently thawing the pipe with warm water and resetting the boiler, but if it continues to freeze, an engineer can insulate or reroute it to prevent future issues. Faulty Diverter Valve In combi boilers, the diverter valve directs hot water either to your taps or to your heating system. If it becomes stuck or worn out, you might notice heating but no hot water, or vice versa. A faulty diverter valve can often be replaced quickly by a Gas Safe engineer, restoring both your heating and hot water supply without needing a full boiler replacement. Pilot Light or Ignition Problems If your boiler’s pilot light keeps going out, or you hear it attempting to ignite without success, it may be struggling due to an issue with the ignition system, gas supply, or flame sensor. Modern boilers use electronic ignition rather than a permanent pilot flame, so if the system fails to light, it’s essential to have it checked professionally for safety. Limescale Build-Up In hard water areas, limescale can accumulate inside your boiler, especially in the heat exchanger. Over time, this restricts water flow and heat transfer, leading to lukewarm water, strange noises, or even complete loss of hot water. Regular maintenance and descaling can prevent this problem and extend your boiler’s lifespan. Airlocks or Sludge in the System If there’s trapped air or sludge in your heating system, it can block water circulation and stop the boiler from heating water properly. This is often more common in older systems or those without regular servicing. Flushing the system or bleeding radiators can sometimes help, but in more serious cases, a powerflush may be required. How to Respond Safely Before Calling for Repairs Before reaching out for boiler repairs in Warrington, Wigan or Bolton, try these simple checks: Confirm your thermostat settings and timer are correct. Check for any error codes or warning lights on your boiler’s display. Ensure your water, gas, and electricity supplies are all switched on. Look at the pressure gauge and note if it’s below one bar. Inspect the condensate pipe for signs of freezing during cold weather. If these steps don’t resolve the issue, it’s time to call a professional. Continuing to use a faulty boiler can worsen the problem or create safety risks. It’s always best to switch off the boiler and seek expert advice. Get Reliable Boiler Repairs in Warrington, Wigan and Bolton Looking for expert help to restore your heating and hot water? TwinSun Heating offers dependable boiler repairs across Warrington, Wigan and Bolton. Our qualified engineers provide transparent advice, efficient service, and lasting solutions. Call us today or fill out our contact form to book your repair visit.
