Cooling Tower Water Treatment System. Proposal shall include annual chemical program to address corrosion, scale inhibition, and algae control as outlined in ASHRAE Guideline 12-2000 7.6.2. Appropriate chemicals to annually disinfect towers according to ASHRAE Guideline 12-2000 7.6.3 must be included in proposal. All Maintenance and/or repair work to the chemical feed stations is the sole responsibility of this contract holder. This includes the pumps, sensors, the feed station itself, and any piping that is associated with the chemical station, excluding the fresh water supply line pre-inlet and power requirements. Closed Loop Water Treatment System. Chilled and hot loops are primarily maintained with a nitrite program. Several new loops are a molybdate program. In addition, three schools operate “ice box” systems with an inhibited glycol program. All loops are set up with 5 gallon bypass pot feeders with 20-25 micron filters. Charleston County School District will maintain in warehouse appropriate chemical/filter inventory for all loops to be prepared for emergency needs. Chemical needs for closed loops are not required for this contract. Any changes or alterations to this schedule are under the complete discretion of the HVAC shop Foreman. Water Testing Requirements. Cooling Tower Testing. All towers will be tested eight (8) times per year in accordance with Attachment A schedule. This will require onsite visit to include inspection, water sampling, and written report within one (1) week of visit to be delivered to CCSD HVAC personnel. AP Tech Groups phosphonate or molybdate tracer, or approved equals, program will be our only consideration. Water test will report conductivity, ph, hardness, alkalinity, appropriate inhibitor levels, and quarterly biological testing (dip slides). Any program established by the contract holder must meet or exceed ANSI/ASHRAE Standard 188-2018, Legionellosis: Risk Management for Building Water Systems that establish minimum legionellosis risk management requirements for building water systems. Closed Loop Testing. All loops will be tested four (4) times per year in accordance with Attachment A schedule. The contract holder will collect water samples with reports and deliver reports via E-mail to HVAC shop. Water tests will report conductivity, ph, and appropriate inhibitor levels-nitrite or molybdate. “Ice Box” loops shall be monitored for glycol degradation to include as minimum conductivity, ph, glycol %, and alkalinity testing.
