How to Restart Your Boiler: 5 Steps to a Safe Reset

Don’t let your boiler freeze you out this winter

Man adjusting boiler
Photo: Westend61 / Getty Images
Man adjusting boiler
Photo: Westend61 / Getty Images
SKILL LEVEL
Easy
COMPLETION TIME
20 minutes
COST
Up to $25
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What you'll need:
TOOLS
  • User manual
  • Flashlight
  • Computer or smartphone (if you have a boiler app)
SUPPLIES
  • Batteries (optional)

It's getting chilly outside, and while turning on the heat, you realize something is up with the boiler. The first step when experiencing heating system issues is a boiler reset. For your safety, it is best to proceed with caution. It requires adhering to the manufacturer's instructions or consulting a professional for clarification. That said, here's a general guide for how to reset a boiler.

Prepping for a Boiler Reset

Common reasons a boiler requires resetting include ignition failures or sensor malfunctions. Resetting a boiler usually doesn't demand specialized tools, but the necessary equipment can vary based on the boiler's type, model, and the particular issue you aim to resolve. The one item you must have is your boiler’s user manual—consider it the paramount tool.

Your boiler’s manual details functionalities, safety protocols, and step-by-step troubleshooting guidance. If you find the manual confusing or are uncomfortable performing the reset steps, consult a local boiler repair specialist.

  1. Locate the Reset Button

    Most boilers have a reset button or switch. It's usually red and on the front of the boiler or the control panel. You may need to refer to the user manual to find the exact location. Press the reset button for several seconds. Afterward, the boiler should reset. If you have a boiler app or a display screen on your boiler, you should get a message if the reset was successful or not.

  2. Turn Off the Power

    Man turning off the fuse box
    Photo: Андрей Клеменков / iStock / Getty Images Plus / Getty Images

    If the boiler still shows an error code, cut off the power supply at its circuit breaker or gas line and wait up to 10 minutes.

    Grab your flashlight if your basement or utility room is a little dark. For an electric boiler, go to your electrical panel and turn off the appropriate circuit breaker. It should be labeled. If not, you must locate the correct one by switching off each circuit breaker until you find the right one.

    To turn off the gas, look for a gas valve that should be nearby. The valve might be red and labeled. When in doubt, talk to a boiler specialist.

    Afterward, you can restore the power and observe whether the error code on the boiler’s digital display or your app vanishes.

  3. Monitor the Boiler

    After resetting the boiler, monitor it to see if it starts properly and runs without issues. Pay attention to error codes or warning lights on the boiler's digital display or app. If there are any problems, note the error codes or messages for reference.

  4. Additional Troubleshooting

    Man reading instruction manual
    Photo: mixetto / E+ / Getty Images

    If the boiler doesn't start or continues to display error codes or issues, consult your user manual for troubleshooting tips. Different boilers may have specific procedures for diagnosing and resolving problems based on the error codes.

  5. Check for Fuel Supply

    What if the boiler is not still working? If it runs on oil, you might be out. Even modestly sized homes need to fuel up once a year. If you refueled recently and you’re still having issues, call a local boiler specialist.

DIY vs. Hiring a Pro 

If you can't reset the boiler or if it continues to malfunction, it's best to contact a qualified technician to diagnose and repair the issue. Attempting to fix complex boiler problems without the necessary expertise can be dangerous and may void your warranty.

The expense of fixing your boiler falls between $200 and $600 on average, although it could reach as high as $1,700  depending on your boiler's specific issue. When you weigh this against the national average cost to replace a boiler—that’s $5,900—it becomes apparent that maintaining your current one might offer a more budget-friendly solution. However, it's worth considering a replacement if your boiler has surpassed the 15-year mark.

Frequently Asked Questions

Attempting DIY fixes can be dangerous. Regular boiler maintenance can help prevent overheating, so schedule professional servicing as a preventive measure. In an emergency, telling occupants to leave the house is a good idea. Then, you can turn off the boiler and the gas or fuel supply. Let it cool naturally, and check the thermostat's settings. Ensure there are no obstructions around the boiler for proper ventilation. Monitor the pressure gauge; if it's too high, bleed the radiators if necessary. During this time, bringing in professionals for troubleshooting is also smart.

Boilers are equipped with multiple safety features to ensure safe operation. These include pressure relief valves to prevent overpressure, temperature high-limit switches to avoid overheating, and flame failure safety devices in gas boilers to cut off the gas supply if the flame goes out unexpectedly. Low water cutoffs prevent operation with insufficient water levels, and pressure gauges help monitor pressure levels. Ventilation and flue systems prevent the buildup of harmful gasses. Boilers often feature error code systems for automatic shutdown during malfunctions and gas leak detection for safety. Regular maintenance is crucial to ensure these safety features function correctly.

Blockages can occur for various reasons, primarily linked to the accumulation of debris or substances within the heating system. Common causes include the buildup of sediment, rust, or mineral deposits inside the boiler or its pipes, hindering water flow and heat transfer. Additionally, air pockets or trapped gasses can impede circulation. In central heating systems, sludge or corrosion within radiators can obstruct the flow of hot water. External factors like frozen pipes in winter can also lead to blockages. Regular maintenance will help prevent blockages and ensure efficient boiler operation.

The absence of heating or hot water, unusual noises like banging or gurgling, and visible water leakage are key signs. Abnormal boiler pressure, flame irregularities (for gas boilers), or pilot light issues may also signal trouble. Frequent cycling, soot or staining, and unusual odors, particularly gas-like smells, should not be ignored. Modern boilers often display error codes or lockout mode upon detecting issues. Uneven heating across radiators and rising energy bills without increased usage can further point to problems. Prompt attention to these signs is essential to prevent further damage and ensure safety.

Yes, cleaning a boiler is essential for its efficient and safe operation. Over time, boilers can accumulate dirt, rust, sediment, and mineral deposits, reducing efficiency, increasing energy consumption, and causing potential breakdowns. Cleaning involves removing these deposits from various components like heat exchangers, burners, and pipes. Neglecting cleaning can also lead to corrosion and decreased life span. Regular, yearly maintenance, including cleaning, ensures optimal performance, lower energy bills, and a safer heating system. It's best to consult the boiler's manual or hire a professional technician for cleaning to ensure the job is done right.

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