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Gas Boiler Maintenance Tips

Gas Boiler Maintenance

Isn’t it frustrating, how you never have a problem with your gas broiler until it is so cold you cannot go without your heating system? The most common problems during the winter months are busted pipes and overworked gas boilers. Not only could this be uncomfortably cold, but it can also lead to expensive maintenance and repair bills.

Below we have given a few gas boiler maintenance tips on how to prevent them happening.

Condensing boiler maintenance

This type of heat is fueled by either oil, propane or natural gas by condensing hot water vapor in the exhaust gas and recovering the heat from vaporization. A condensing boiler is increasing in popularity because they help cut cost on both the electric and gas bills.   Most generally when a condensing boiler is installed it comes with a list of maintenance that should be checked, daily, monthly and yearly.


Check around and under the boiler for water leaks.

Ensure the boiler area is free of any obstruction or combustible materials.

Check pressure and temperature readings and make sure they are within the designed range.

Keep ventilation clear and does not become blocked with snow, ice, or debris.

Check to ensure the combustion chamber air opening is unobstructed


Check to make sure the flue gas vent piping and combustion air piping show no signs of blockage, leakage or deterioration.

Look for signs of weeping or leakage from the boiler relief valve and discharge valve.

Check the condensate drain system (drain line, PVC fittings and drain trap) for blockages (condensing boilers).


Inspect and clean the boiler heat exchanger. Flush clean and inspect condensate system as necessary

Inspect and clean ignitor, flame sensor and burner assembly

Make sure the air inlet and vent terminations are clear and not obstructed

Routine gas boiler maintenance


Clean the combustion chamber, the heating exchange, and the fuel burners regularly. Check the heat exchange for leaks.

Check the color of the pilot flame to make sure it is blue. If it is orange or yellow, the gas boiler is not burning properly.

Make sure the radiator and fan belt are clean of dirt and dust. Ensure there are no cracks in the belts.

Regularly change and maintain the filters. If a filter is clogged, it can affect the heating system. 

Lubricate and oil the gas boiler motor. 

Check and seal all ventilation for cracks and holes. Pay particular attention to pipes, ductwork and the chimney.

Perform a regular combustion check for efficiency test to monitor how much exhaust is filtered into your home. Perform a carbon monoxide test frequently.  

Check the high limit and pressure relief valve for normal function by running your hand over the drain lines to see if they are hot. If they are hot, this means that the valve is normal and opening properly and hot water is flowing. Press the pilot button to check if it releases to check the high limit control valve.


Usually, routine cleaning and leak checks can be done without a service call. 

Dirt and dust build up are the number one reason for broken systems and repair calls.

Cycle the gas boiler once a month even in the summer to maximize efficiency.

Replace old mechanical thermostat(s), with digital thermostats for the central heating unit. This is an inexpensive improvement that can pay off over time.

Replace old manual air vents with automatic float type vents to improve system performance.

Annual central heating tune ups eliminate breakdowns due to neglect, prolong the life of gas boiler and reduce energy costs.


Professional boiler servicing companies are trained to maintain and perform home boiler repair. It can be dangerous to perform boiler repairs without the help of a professional. It is easy to make a mistake while fixing a leak or break that could cause a carbon monoxide or water leak. Carbon monoxide is dangerous and can be deadly. Install a carbon monoxide detector to help safeguard your home and give you peace of mind. 

If you own a boiler older than 25 years old, you might need to invest in updating your boiler to a newer model with safety controls.

Do not ignore leaks. Any leak, even small leaks is a precursor of a bigger issue.

There is never a right time for a boiler to break down. Even if you have made sure to do constant routine boiler maintenance, breakdowns usually happen at the most opportune moment with no access to hot water or boiler service repair services. Boiler cover insurance is one way to help in these situations.

Routine maintenance may vary between different furnace brands, but the maintenance tips above are basic tips. While most of the maintenance tips can be done by yourself, there are a few you may need help. Ask an HVAC Expert to help guide you through your maintenance questions.  

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