What to Do If a Boiler Overheats

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What to Do If a Boiler Overheats

Gone are the dangerous days of exploding overheating boilers, in the past 10 years there have been only 127 deaths from overheating boilers. It translates to only 13 fatalities per year in the United States. Nowadays modern boilers are designed to be extremely safe and durable – but though overheating may not be so dangerous, it still causes problems.

So what are the causes and what can you do about it?

Blocked Heat Exchanger

With continued usage, limescale, rusts, dust, and other debris accumulated from the system collects on the exchanger’s heat. The accumulation, in the long run, blocks the system. In return, the materials restrict the flow of water across the heat exchanger leading to pressure build-up. As the pressure increases in the boiler, the heat builds up and eventually makes the entire system overheat.

You need not worry if you have modern boilers. They have the latest safety controls that cause the boiler to shut in case of overheating automatically. If you have an old model (pre-2010) we recommend turning off the boiler immediately when you realize the problem.

A certified maintenance specialist will examine the system and fix it. In most cases, the specialist power flushes the boiler system removing the debris and any blocked material there. That way, they clear the way for seamless water flow, thereby reducing the pressure and eventually the heat.

Failed Thermistors

A thermistor is a thermally sensitive specialized resistor. It senses and measures the temperature changes in your boiler and related systems. It helps the PCB know whether to increase or reduce the heat according to the statistics sent.

The following are situations when the thermistor can fail:

  • Mechanical separation of the lead material and resistors elements
  • Aging of the thermistor
  • Short circuit

If the boiler thermistor fails, your water risks getting too hot and result in the boiler overheating. It could also result in excessive consumption of electricity or fuel. In such cases, call a qualified boiler engineer to replace the component, and everything will go back to normal.

Faulty Pump

The boiler pump circulates the water in your pump’s central heating system. If it develops faults, it will not release water promptly, leading to pressure build-up, this causes the system to overheat.

In such cases, you need to replace your pump and restore the system to standard functionality. We recommend that you hire a fully-qualified heat engineer for such purposes.

What to do About an Overheating Boiler

In most cases when your modern boiler overheats, you’re going to need to get a professional repair technician to solve the issue. Your boiler may continue to operate, but under more strain – which isn’t good for it; the boiler may also shut off completely and then you’ll have no hot water or heating, so it’s best to call for a service sooner rather than later.

Easy signs to look out for:

  • Switching off automatically or cutting out – sometimes overheating
  • Boiler wont shut off at all – possible overheating

Are Overheating Boilers Dangerous?

Though very are, your overheating boiler could be dangerous. So don’t take it too lightly. In some cases overheating boilers lead to ‘runaway boilers,’. This is a significant danger for both users and the emergency services responders. Overheating boilers develop immense pressure when the pressure relief valves fail.

In old modeled boilers, the high pressure could lead to explosions. Modern boilers have control measures. This helps them to withstand the pressure of up to 20PSI. In most cases if the pressure is too much they’ll just shut down, but in rare cases they can still explode.

Do I Need An Emergency Boiler Repair?

It’s never a bad idea to consider overheating boilers as an emergency. After all if you aren’t an expert you can’t know the seriousness and severity of your issue, so it’s always good to seek peace of mind from a professional. Please do not attempt to repair gas appliances with some DIY methods of your own. If you detect overheating or any other problems with your boiler, turn it off. You can then call a fully certified boiler repair specialist to detect and resolve the issue.