How to Purge an Oil Condensing Boiler

An oil condensing boiler removes heat from the flue and then uses the waste heat to warm up the cold water in the boiler. The boiler creates water vapor that drains out of the system. Oil condensing boilers typically heat water in a short period of time and are considered high efficiency systems. The boiler should be purged on a regular basis to remove any dirt or sediment that has settled into the bottom of the water tank, which can slow down efficiency.

Hose
Bucket

Instructions

- 1
  Disconnect the power to the boiler by unplugging the power cord then wait for it to cool down.
- 2
  Connect a hose to the drain valve and set the other end of the hose into a large bucket or a nearby drain.
- 3
  Open the drain valve and let the boiler drain out through the hose. Open the fill valve once the water is flowing out of the drain valve.
- 4
  Let the water continue to drain out of the boiler until it flows steadily with no air bubbles and there is no sound as the water drains.
- 5
  Close the drain valve and then the fill valve. Allow the boiler to refill as normal and then restore power.

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