Cold water systems

First, one pump running in a parallel system tends to suffer from cavitation because operation to the right of the BF.P indicates that the NPSHr of the pump rises drastically. To survive this condition, you should use dual mechanical seals on these pumps. Dual or double mechanical seals can withstand cavitation better than a single seal. There is a discussion on this in the mechanical seal chapter of this book. Many engineers perceive that parallel pumps are problematic becau.se they appear to suffer a lot of premature seal failure. Parallel pumps deserve double seals even if it s only a cold water system. 

From a basic physics standpoint, a circuit is a complete loop. Electric current can flow only if it returns to its source, i.e., completes the circuit. The path tlirough which tlie current returns to its source is called the "retum or ground. The reason for the tenn "ground is tliat the ctirlh is literally used to provide the return patli no matter what distance separates tlie equipment from the power source. Ground comiections can be made to a cold water system as its components provide a reliable, low-resistance patli for contact witli tlie earth. 

Where glycols are added to both hot and cold water systems, it is common for the glycol to be supplied neat, preinhibited and buffered (although the glycol also may be supplied in a diluted and ready-to-use form). This formulation is an example of a type produced as an glycol inhibitor-pack concentrate ... 

The newly developed ACTIV-OX chlorine dioxide system has effectively delivered continuous low levels of chlorine dioxide which were effective in controlling Legionella in a hot and cold water system without the need for prior disinfection. 

ISO 10508 1995 Thermoplastics pipes and fittings for hot and cold water systems. 

Cold water systems of galvanized pipes, tanks, and cylinders—together with galvanized fittings—were standard in many countries for about a century. In many cases the pipes and fittings lasted the life of the house tanks and cylinders, even in scale-forming areas, tended to leak after 20-40 years. 

Juchniewicz, R., Jankowski, J., and SzukaLski, J. (1991). Electrochemical protection of domestic hot and cold water systems. Mater. Performance, January, pp. 22-26. 

Apparatus for disinfection (only for cold water systems). See Fig 27.4... 

Cold water systems usually cannot be steamed. Instead chemical disinfection or disinfection using ozmie is customary. An important benefit of ozone treatment compared to other chemical methods is that it can be executed automatically. 

Corrosion and corrosion damage, basic terms in corrosion science - Corrosion in hot and cold water systems in domestic installations) (in German), p. 7 Deutsche Gesellschaft fur Metallkunde, D-Oberursel, 1984... 

Schematic diagram of 1-2 shell and tube heat exchanger for the hot-water-cold-water system is shown in Figure 4.34.

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