Day Tank for a Diesel GeneratorDay Tank for a Diesel Generator | Critical Facilities - This is a photo of a generator day tank for a diesel generator. The tank has floats inside that keep the fuel level automatically topped off in the tank so when the generator starts there is a fuel supply ready to go. As the generator consumes fuel the pump activates and resupplies the tank to keep the generator fueled and running.

Day Tank for a Diesel Generator | Critical Facilities

A pump will pump the fuel from the main storage tank to supply the day tank so the generator will have a day (give or take depending on the size of the generator and the load on the generator) amount of fuel to run under normal load. The controls for the day tank are more complex than other tanks which supply fuel for generators. An automatic day tank has alarms for the fuel level – alarms for both too low and too full alarms – and manual tests procedures for testing the pumps and fuel level floats.

Diesel supply piping is painted yellow and has a return and a supply pipe for keeping the flow of the diesel through pipe even in cold weather. In cold weather, diesel fuel can turn into a gel and cause issues with running the generator.

Day Tank for a Diesel Generator | Critical Facilities

Day tanks can also be fitted with electric heaters to keep the diesel fuel from gelling in the winter. Other ways to prevent diesel fuel from gelling is additives in the diesel fuel that prevent gelling in extremely cold weather. Some diesel fuel systems for large generators have scrubbers that will run specified or programmed time of the week.

The fuel scrubber is used to filter and clean the fuel from impurities that end up in tanks like water and diesel sludge. This ensures the generator receives quality fuel. No fuel scrubbers are pictured here.

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Day Tank for a Diesel Generator

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