Trane SYS-APM001-EN manual Contingency, Minimum capacity required, Type and size of chiller

System Issues and Challenges

Contingency

Today, many organizations have contingency plans for critical areas of their business. Some deal with natural disasters and others with the loss of power in critical areas. However, few have actually taken the time to think about what a loss of cooling would mean to their facility. If the cooling system failed or was suddenly grossly undersized due to weather, etc., how would that affect business? What financial risk would be involved with a loss of cooling?

Cooling contingency planning is intended to minimize the losses a facility may incur as a result of a total or partial loss of cooling. It allows a building owner to act more quickly by having a plan in place and by proactively preparing his or her facility to accept temporary equipment. Although a number of facilities are prepared after the construction phase, the construction phase provides an easy and cost-effective opportunity to prepare a facility and is a logical time to provide water stub outs and electrical connections. This helps to keep costs down and reduces the need to shut down existing equipment to make necessary building preparations.

Cooling contingency planning is the process of preparing for a loss of cooling while in a non-emergency situation. This allows common sense, rather than panic, to prevail during a critical event. The following topics are general and broad in scope. They provide a sense of what is involved in the planning process. Contingency planning itself is very detailed and situation-specific.

Minimum capacity required

It is important to first identify the minimum capacity required. With multiple chillers in a facility, it may be acceptable to have less tonnage in an emergency situation. For example, a facility’s chiller plant may consist of 1,800 tons [6,330 kW], but the minimum tonnage required may only be 1,200 tons [4,220 kW]. Therefore, it is also important to identify the plan of action if Chiller 1 fails, if Chiller 2 fails, if Chillers 2 and 3 fail, and so on.

Type and size of chiller

The type and size of contingency cooling required by a facility are determined by several factors. In turn, the choice of chiller determines how the facility is prepared. Examples of parameters that determine the chiller are:

•Electrical requirements

•Ease of installation (air-cooled chillers are easier to set up)

•Location or available space

•Comfort or process cooling

SYS-APM001-EN Chiller System Design and Control 81