What would happen if some of the unloaders in a multi-cylinder reciprocating compressor fail to operate?

If some of the unloaders in a multi-cylinder reciprocating compressor fail to operate, the chill water temperature will increase. This occurs because the unloaders are responsible for regulating the flow of refrigerant; if they are not functioning, the compressor cannot effectively manage the refrigeration cycle. As a result, it may not remove heat as efficiently, leading to an elevation in chill water temperature.

The other possibilities involve scenarios that might not directly stem from unloader failure. For example, overheating might occur as a secondary consequence, but it is not guaranteed. Leakage of refrigerant and automatic system shutdowns are typically linked to more severe failures or different malfunctions within the cooling system. Thus, the primary immediate effect of unloader failure is indeed the increase in chill water temperature.