Which device can be connected to a water column?

A water column is a device used to measure the pressure of a fluid in a system, and it typically utilizes a scale to indicate the height of the water column, which directly relates to the pressure exerted by the fluid. The steam gauge, which is designed to measure steam pressure, can be connected to a water column to provide an accurate reading of steam pressure in a boiler system. By connecting the steam gauge to a water column, the gauge can utilize the water level to translate pressure measurements effectively.

In contrast, the other devices mentioned serve different functions. A water heater is primarily used for heating water and does not measure pressure. A heat exchanger transfers heat between two or more fluids and also does not provide pressure readings. A condensate tank collects condensate from steam systems, but it does not inherently measure pressure like a water column connected to a steam gauge. Therefore, the steam gauge is the appropriate device that directly relates to the function of a water column.