HE Boiler Serice

High Efficiency Boiler Annual Maintenance

Does a high efficiency boiler need serviced every year? ....... NO!.....
That is what most homeowners believe. Of course they should be serviced every year, I was just kidding.


Why should an annual service be performed every year?

An annual service does not only mean cleaning the boiler as it may not require to be cleaned every year. The annual service is to verify all the safeties are working properly. A visual inspection of the air vents or pipe joints have not started to leak. Visually check the vent and air intake pipes for any type of blockage. Open the relief valve(s) to make sure it will work if needed. This is necessary. If the relief valves have not been checked in a few years the relief valve may leak when tested and will require a replacement. If check annually it will open and seat for a lot of years. Simply put, an annual service is to find and correct small problems before they become larger more expensive problems.

High efficiency boilers have narrow flue passes and small water passages. They do need serviced every year. I have heard service tech"s say that they will go out and clean a high efficiency boiler and when it is opened there is no dirt in the heat exchanger.

Let's not think of cleaning every year but preventive maintenance every year. Cleaning the heat exchanger is only one part of the annual service. I do not want to minimize the cleaning of the heat exchanger. On water tube heat exchangers, as important it is to clean the tubes it is equally or more important to clean between the water tubes in the heat exchanger. These gaps are only about as wide as the thickness of a credit card.

If this is not done the boiler will move less air through the heat exchanger. What is the result of this? Less heat. The gas input is controlled by the amount of air passing through the heat exchanger. If the air is restricted to flow by a dirty heat exchanger the less gas can be pulled through the gas valve. The heat exchanger should be brushed, cleaned between the tubes, and washed to be cleaned. After that process is done do the following.

  • Check all safety's
  • Open relief valve if it leaks replace it. It won't leak normally if annual maintenance is performed. If not opened in years it probably will.
  • If the boiler is a combi, flush the DHW heat exchanger
  • Check sensor values
  • Clean/replace flame sensor and ignitor. Verify proper gap on ignitor
  • Clean out condensate lines and condensate pump
  • Replace condensate neutralizer, replace stone if needed
  • Verify vent and air intake pipes are unobstructed
  • Check incoming gas pressure in a static state when the valve opens and in high fire
  • Perform a combustion test to manufactures spec's. In number are not spec's but instead a range keep O2 middle of the road or closer to the low side.

    As this is not a complete list it is a general guideline.

    Now is the time to look for early detection of problems like air vent leaks, water leaks at fittings, water pressure problems ETC. before they become a larger expensive repair for the homeowner.

    Disclaimer: The information found on this web site is for informational purposes only. All preventive maintenance, service, installations should be reviewed on a per-job situation. Any work performed on your heating system should be performed by qualified and experienced personnel only. Comfort-Calc or its personnel accepts no responsibility for improper information, application, damage to property or bodily injury from applied information found on this web site.