TOP 7 Common Gas Boiler Faults

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Though modern boilers are very reliable, one day they break down. A logical approach to gas boiler faults helps to identify the problem earlier and fix it without additional money expenses. Common faults are associated with all type of gas boilers that contain many complicated components, which all have the potential of breaking down during the lifespan.

gas boiler faults

So, what are the commonest faults we usually deal with? Are they serious or minor? Can they be repaired or require boiler replacement? Let’s see.

Common Gas Boiler Faults to Deal With

  • No hot water or heat. For many of us this problem seems to be the most serious one, though it is not true. If the boiler does not produce any hot water or heat, don’t start to panic, as this is a usual case. Among the number of triggers that can contribute to its occurrence belong: failure of motorized valves, broken diaphragms or airlocks, low water levels and issues with the thermostat.
  • Boiler thermostat turned down. All you have to do is to turn it back. It can be turned down by accident by someone or on purpose and you’ve simply didn’t notice it or forgotten. Many people turn it down for summer period and turn on for colder times. Check whether the power to the boiler stat. If it is, but it doesn’t do the job, it must be replaced. If there is no power, the problem is in the line.
  • Condensation pipes take condensation from the boiler to the drain that is outside. During cold periods the pipe is very prone to freezing, which may lead to the appearance of blockages that back up to the boiler and cause boiler problems. When there is a bubbling sound that comes from the boiler or the condensation pipe, this becomes a very first sign that the condensation pipe has frozen.
  • Losing pressure is attributed to a water leak in the system, which is the commonest reason for pressure loss. The pressure may go down because of the pressure relief valve that is triggered by the expansion vessel failing. To deal with this gas boiler fault one should replace the pressure relief valve and recharge the expansion vessel with air.

boiler faults

  • Circuits boards in gas boilers can fail as well. They control the whole work of the boiler, so when they fail, the boiler fails as well. In most cases their failure is the first sign of a more serious problem – a pipe leak can put water on the circuit board causing boiler breakdown. We also wrote about choosing gas boiler breakdown cover.
  • Loud banging noise appears when the pump is not working or comes to the end of its working life. What’s the way out? You should either replace it or free. Make sure you’ve checked whether bypasses fitted are open. As a rule, the noise is loud and sounds like there’s someone thumping the boiler.
  • Radiators don’t get hot when the central heating system is on. This happens due to the pipe work that has caused sludge to gather in the system. It prevents the free flow of water to the radiators.

In case you’re not absolutely sure as to what gas boiler fault you are facing, consult a professional to prevent further complications and great money waste.