Posted by Janet on April 14, 2000 at 17:38:08:
In Reply to: Boiler water level shrink & swell posted by Mike on April 14, 2000 at 08:21:53:
: I'm having a problem with my boiler water level.
: Basically, the level slowly shrinks & swells, which in turn
: causes my feed pump to short cycle. The level doesn't fluctuate violently,
: it just rises & falls very "lazily" but consistently.
: Any help or ideas on what to check would be greatly appreciated.
Mike:
Shrink and swell phenomena are not typically due to high TDS in the boiler. Shrink and swell are typically associated with pressure fluctuations with your system load. The rate and amount of level swing will give you an indication of the severity of the load fluctuations.
High TDS decreases the surface tension of the boiler water and increases the probability of foaming on the surface. Either one could cause carryover by itself, but coupled together they obivously worsen the condition.
You should investigate your control system and your loads carefully to determine the cause since more than one source can be contributing to the shrink and swell.