Start-up and Shutdown Procedures
For the next section of our MPP series we will talk about the Start-Up and Shutdown procedures that must be included in an MPP. As this is considered a very important element of the Maintenance Program & Plan the Department of Health has broken these requirements into its own statute of code that correlates with the MPP requirement (RCNY 8-06).
To start the MPP must reference procedures that cover the following Start-Up Requirements:
- The tower must be cleaned and disinfected anytime a tower is offline (drained of water) for more than 5 days. This cleaning must be performed within 15 days of first seasonal use of the tower
- A legionella sample must be pulled before any tower offline for more than 5 days is put into use
- A pre-startup inspection must be performed by a qualified person before being put into use
These requirements are in place to lessen to the greatest extent feasible the possibility of a dangerous legionella condition. As it is possible with dead-legs or low-flow areas of a cooling tower to have water that is sitting stagnant while the system is not in use. Without proper procedures these conditions can harbor high amounts of bacteria if not disinfected and cleaned when putting a cooling tower into use.
System shutdown must include the following:
- Perform adequate system shutdown according to cooling tower manufacturers specifications
- (Typically as part of a manufacturers shutdown these common items would be included)
- Decommission and lock-out all tower circulation pumps and fans
- Valve off and drain/winterize the fresh water makeup line
- Drain the cooling tower of all water and drain the tower piping below the roof line to prevent freezing
- Leave all tower drain valves in the open position to minimize accumulation of water in the tower during the winter season
- The other requirement is that the system must be protected from offline contamination
If all of the above items are covered, any cooling tower will be much safer and less likely to harbor harmful bacteria.
For assistance in creation or management of an MPP please contact The Metro Group at 718-729-7200
MPP Series Part 1: https://www.metrogroupinc.com/uncategorized/understanding-a-cooling-tower-mpp-series-part-1/
MPP Series Part 2: https://www.metrogroupinc.com/uncategorized/understanding-a-cooling-tower-mpp-series-part-2/
MPP Series Part 5: https://www.metrogroupinc.com/uncategorized/understanding-a-cooling-tower-mpp-series-part-5/