Losing heating or hot water without warning is one of the most disruptive boiler faults, especially in the colder months. Our Gas Safe registered emergency boiler engineers cover Cardiff 24/7 and respond fast when your boiler stops producing heat or hot water. There are many possible causes — a failed ignition or pilot, a faulty diverter valve that prevents hot water reaching the taps, a seized pump, a frozen condensate pipe during cold snaps, low system pressure, a tripped thermostat, or a fault on the boiler's control board (PCB). Because the symptoms overlap, accurate diagnosis matters: replacing the wrong part wastes money and leaves you cold. We carry diagnostic equipment and the most common spares on every van, so a high proportion of no-heat callouts are fixed on the first visit. We work across all major boiler brands and both combi and conventional system setups found in Cardiff homes, from CF1 in the city centre to CF14 and CF24 in the suburbs. Every job starts with a fixed-price diagnostic from £85, with no call-out fee, so you know the cost before we begin.
We check the boiler display code, system pressure, gas supply, and electrical controls to isolate whether the fault lies with ignition, the diverter valve, the pump, the PCB, or the condensate run.
Once the cause is confirmed, we explain the fault in plain English and give you a fixed price for the repair before any work starts — no obligation to proceed.
We carry common spares including diverter valves, thermistors, pumps, and ignition components, so most faults are repaired on the first visit. We thaw and re-route frozen condensate pipes where needed.
We re-fire the boiler, confirm both heating and hot water are working correctly, check system pressure, and advise on preventing a recurrence.
Emergency no-heat and no-hot-water diagnostics start from £85 fixed price, with no call-out fee and no out-of-hours surcharge. Many simple faults — re-pressurising the system, thawing a condensate pipe, or replacing a minor component — are resolved within the diagnostic visit. Where a larger part such as a pump or PCB is required, we quote a fixed price before proceeding so there are no surprises.
Common causes include a faulty diverter valve, low system pressure, a seized pump, ignition or pilot failure, a frozen condensate pipe, or a control board fault. Our Gas Safe engineers diagnose the exact cause on site rather than guessing, so the right repair is carried out first time.
If you have no hot water and no heating — particularly in winter, or in a home with young children, elderly residents, or anyone who is unwell — we treat it as an emergency and aim to attend the same day, 24/7, across Cardiff.
If your boiler pressure reads below 1 bar, you can often top it up using the filling loop, following your boiler manual. If pressure keeps dropping afterwards there is likely a leak or a faulty pressure relief valve that needs professional attention. Do not attempt any work involving the gas supply yourself — that must be done by a Gas Safe engineer.
No. We charge the same fixed diagnostic price from £85 whether you call on a weekday, in the evening, at the weekend, or on a bank holiday. There is no call-out fee and no out-of-hours surcharge.