How To Properly Maintain Your Deaerator

Deaerators are a key component to many boiler systems that require regular maintenance to ensure long and efficient equipment life. The primary purpose of a deaerator is to remove dissolved gases such as oxygen and CO2 from the water while also preheating it before it feeds into the boiler. This helps prevent oxygen pitting inside the piping and boiler. So, what are the key steps to maintaining your boiler’s deaerator?

Corrosion on the Tank

Corrosion is one issue that is easily preventable and should be caught early to reduce the risk of more significant problems. Often times leaking pipe outside of the tank cause corrosion issues on the exterior of the tank. This can become a serious issue if neglected and should be addressed as soon as a leak is spotted. Be sure to closely inspect your system on a regular basis and fix leaks as they appear.

Cleaning the Components

The water and steam that pass through the tank are normally of high purity. This means the necessity for cleaning should be infrequent. However, the interior of the tank, spray or tray assemblies should be inspected at least annually for any evidence of corrosion, scaling or other damage.

Be sure to check the spray valve nuts are tight with no evidence of leakage under the gasket. If you start to experience new or unusual noise from the deaerator, the spray valve is a good place to start looking. If the spring breaks within this nozzle the valve can remain open, which will cause water hammer when the supply valve comes on. With any style of deaerator, if oxygen scavenger usage increases over time or a marked decrease in deaerator performance occurs, this could indicate issues with the way the deaerator is being operated, or it could indicate something internally is damaged.

Water Hardness Test

Test water hardness regularly to ensure the water going into the deaerator isn’t bringing in unwanted minerals. If you are unsure what your makeup water hardness should be, consult your boiler water chemistry provider.


Strainers on the deaerator are frequently installed on the pump inlet to protect the pump from debris. These should be flushed regularly (if a valve is present) and should be thoroughly cleaned and inspected on an annual basis. This will prevent blockages from reducing the flow of water to the pump, causing flashing and severe pump damage.

Chemical Pump Maintenance

You will want to verify daily that the pumps feeding chemicals into the system are working properly. It is imperative to use the appropriate chemical treatment while operating your steam system. If either of these items is neglected it can result in corrosion or scale damage inside the boiler system.


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Float Switch Test

It is important to take the time to occasionally check the float level control operation to confirm that the float is moving freely. These float operated controls should be blown down routinely. You should also ensure the level controls are filling to the appropriate level and will turn off the pumps for low water.

Gage Glass

This component of the system should be kept clean to allow for a proper visual inspection. You will want to look for etching, thinning or damage while the unit is cool. It is recommended that if any damage is found or the water level is not easily identifiable, replace the gage immediately.

Need Help?

While this is a great place to start, be sure to follow the manufacturers recommendations for maintenance to ensure your boiler system runs as efficiently as possible.  If you need help maintaining your boiler system reach out for a free estimate, call us at 1-800-237-3141 or chat with an agent. Our team is here to help!


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