UFC 3-240-13FN
25 May 2005
Table 3-21. Troubleshooting Boiler System Water
Problem
Recommended Solution/Possible Cause
Hardness in feedwater
1. Check softener
2. Possible leak into condensate system
1. Change in amount of condensate return
Change in overall treatment
2. Change in blowdown control
levels
3. Change in overall chemical feed rate
1. Hardness incursion
2. Loss of caustic feed
Loss of alkalinity
3. Excessive blowdown
1. Hardness incursion
2. Loss of chemical feed
Loss of scale prohibitor
3. Excessive blowdown
1. Loss of sulfite feed
2. Poor deaerator operation or influx of oxygen
Loss of sulfite
3. Excessive makeup and loss of condensate
High conductivity (>25
Carryover due to misting, foaming, or priming
mhos) in steam
Excessively high TDS, alkalinity, or chemical
Foaming carryover
treatment
Operational problem with excessive load demands,
Priming carryover
feedwater and level control problem, uneven firing
patterns
Misting carryover
Defective mist eliminators
3-4.2.1
up wet will already have adequate excess levels of sulfite and alkalinity (see paragraph
3-5.4). Upon adjusting the water level and firing up the boiler, feed all chemical
treatments as normally added, except for sulfite and alkalinity supplement. There is no
need to feed these treatments until blowdown results in reducing their levels. Then add
chemicals in the amounts required to reach normal maintenance levels.
3-4.2.2
up dry (see paragraph 3-5.3) can be filled with feedwater to their normal operating boiler
water level. The start-up dosage of sulfite and alkalinity supplement (caustic or soda
ash) can be fed along with the standard chemical treatment feed rates to obtain normal
levels of water treatment chemicals. It is necessary to achieve proper sulfite and
alkalinity levels in the boiler water to control corrosion while the COC is increased to
normal operating levels. The sulfite concentration should be at least 20 ppm (SO3), and
the alkalinity level should result in a pH of about 11.0.
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