Don't understand how it works, given it by a friend. no instruction maunal with it, I put in 10 cups of water and truned on the switch and nothing is happening?

I can run over the general instructions for you.
-BEFORE plugging in, with a pot in place under the filter basket, pour through enough water until it flows from the basket.
-Then (and only then) is it safe to energize the heater inside.
-Once the brewer reaches brewing temperature put your coffee in the filter and pour through one pot of cold water and brew.
As recommendation I would say to pour through a little water before brewing in the morning (or anytime the brewer has sat overnight) as there may be some short potting due to evaporation. This will also assure that you are getting fresh water in your brew. This brewer has a reservoir that holds probably 2 or so pots of hot water. If the heating element is energized without water there is a good chance of burning up the heating element. I can run over the general instructions for you. -BEFORE plugging in, with a pot in place under the filter basket, pour through enough water until it flows from the basket. -Then (and only then) is it safe to energize the heater inside. -Once the brewer reaches brewing temperature put your coffee in the filter and pour through one pot of cold water and brew. As recommendation I would say to pour through a little water before brewing in the morning (or anytime the brewer has sat overnight) as there may be some short potting due to evaporation. This will also assure that you are getting fresh water in your brew. This brewer has a reservoir that holds probably 2 or so pots of hot water. If the heating element is energized without water there is a good chance of burning up the heating element.

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