25 May 2005
= ([125 123]/125) x 100 = 1.6% after 4 months
b) The monthly loss based on the 4-month result is calculated:
1.6% over 4 months = 0.4% per month
This loss is less than 1% per month and not excessive.
c) If the concentration had dropped to 123 ppm after 1 month, the loss would
Loss = ([125 123]/125) x 100
= 1.6% after 1 month
d) The monthly loss is calculated:
1.6% over 1 month = 1.6% per month
This loss is greater than 1% per month, and the system should be inspected
Procedures for Layup of Hot and Chilled Water Systems. Follow the
procedure for wet layup of operational boilers described in paragraph 3-5.4. Note these
For hot water systems, completely fill the hot water generator and
expansion tank should not be filled.
For all steel systems using the sulfite-caustic soda program, increase the
pH to 11.7 with sodium hydroxide (caustic soda). Add sodium sulfite to a
level of 100 ppm (as SO3).
Treat chilled water systems using the nitrite-borax or molybdate-caustic
soda treatments with appropriate chemicals to maintain levels required for
Test monthly for treatment chemicals and check water levels.