Which sequence correctly describes a typical startup sequence for a chilled water plant?

Which sequence correctly describes a typical startup sequence for a chilled water plant?

• A. Start cooling tower first, then pumps, then chiller compressors.
• B. Verify flows; start primary/secondary pumps; start chiller compressors after head pressure is achieved; bring cooling tower on; check sensors and interlocks.
• C. Start chiller compressors before pumps.
• D. Verify pressures only; no pumping or chiller start.

Answer: (B)

A safe, reliable startup of a chilled water plant relies on establishing proper water flow and pressures before loading equipment. Start by verifying that flows are present and within design, which confirms the system can actually circulate water. Then bring the primary and secondary pumps online to establish that circulation throughout the loop. Only after there is adequate head pressure should the chiller compressors be started, to avoid deadheading the compressor and potential damage. Once the chiller is running, bring the cooling tower on to reject heat, and finally check sensors and interlocks to ensure all safety checks and control sequences are satisfied. This order protects equipment, ensures effective heat rejection, and confirms that all safety protections are active. Starting the tower too early, starting the chiller without confirmed pumping and head pressure, or skipping the actual pumping and flow verification would risk damage and unsafe operation.

A safe, reliable startup of a chilled water plant relies on establishing proper water flow and pressures before loading equipment. Start by verifying that flows are present and within design, which confirms the system can actually circulate water. Then bring the primary and secondary pumps online to establish that circulation throughout the loop. Only after there is adequate head pressure should the chiller compressors be started, to avoid deadheading the compressor and potential damage. Once the chiller is running, bring the cooling tower on to reject heat, and finally check sensors and interlocks to ensure all safety checks and control sequences are satisfied. This order protects equipment, ensures effective heat rejection, and confirms that all safety protections are active. Starting the tower too early, starting the chiller without confirmed pumping and head pressure, or skipping the actual pumping and flow verification would risk damage and unsafe operation.