Low Pressure Heating Boilers 2006
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This has certainly been an unusual heating season. January gave us days of 60 degrees Fahrenheit, then winter started and it was a very mild one.

As a result, your boiler has had a varying load. When these warm days occurred many of you were at idle or shut down. The next day you were back at full load. When these conditions occur you take on considerably more makeup water than normal.

When I review the field test reports I have seen higher total solids and huge fluctuation in treatment readings. Since spring is upon us you need to take some action now, so that we see clean boilers when you open for inspection.

1) Increase your bottom blowdown about 20%. It helps if you blowdown when the boiler is on Low Fire or Idle. This allows suspended solids to fall to the bottom.

2) Keep your boiler treatment levels at the high end of the range.

P Alkalinity - 500 - 600
T Alkalinity - 700 - 800

Or

Phosphate - 50 - 60

3) Watch the sulfite level, this is the oxygen scavenger. When a boiler shuts down, a vacuum can occur which brings in more oxygen. Increased makeup also brings in more oxygen.

Keep Sulfites @ 60 - 80 ppm

Daily testing is important in conditions like this.

Since we can’t change the weather we need to work with it.


Preparing A Boiler For Waterside Inspection

Your boiler should be opened once per year for a thorough inspection of the waterside. This inspection will show you how effectively the water treatment program is working.

During normal operation, the treatment program conditions the suspended solids so that they fall to the bottom of the boiler and are removed through blowdown. When you shut down and drain the boiler, this sludge may settle and bake on the tubes. The resulting deposit makes an objective and thorough inspection difficult.

I recommend the following procedure:

1) 5 – 7 days before scheduled shutdown, double the bottom blowdown rate.

2) Increase the Boiler Treatment (Sludge Conditioner) level to maximum reading.

3) Maintain the sulfite level in the high range.

4) 24 hours before shutdown, decrease the surface blowdown and increase the bottom blowdown to 5-10 second blows every two hours.

5) After you have stopped firing, continue frequent short blowdowns.

6) Blowdown the water columns and gauge glass regularly.

7) When the boiler is cool…..drain and IMMEDIATELY wash out any remaining sludge in boiler and water columns.

NOTE: Always cool and drain the boiler in
accordance with the manufactures
specifications.

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