How to Set flow amount on Bunn STF-20 - Bunn -O-Matic Corp. 2 Warmer Auto Brewer Black

Hell and good day,

this simply means that it need to be service

Thanks for coming.

This could be an issue with the wiring of the fill and brew valves or it could be an issue with the control board. When you draw water off, the machine should replace the same volume of water by opening the fill valve. If the brew valve is opening at the same time, tgen there is an issue. I recommend placing a service call.

Clean with white vinegar, run it through 3 times, then you are set.

These tanks can't actually be overfilled since all water poured in displaces the exact same amount of water coming out the spout. So, whatever amount of water you pour in, will be the same amount of water that flows to your pot minus the amount absorbed by the coffee grounds and filter.

Your problems sounds like an undersized (Non Bunn) filter, or clogged brew basket. To verify this, try pouring in only half the water for your brew cycle and wait for it to finish dripping, then pour in the rest. If no overflow has occurred, you simply have the wrong type of filter. If overflow begins again, you have a clogged brew basket, since no Bunn can flow too fast for the brew basket to keep up with it.

This is because Bunn filters are manufactured differently than generic store bought paper filters. They will flow faster, brew cleaner and stand up better than normal generic filters.
Remember, Bunn makes their OWN filters for good reason.
They made the first, best paper filters for drip coffee pots, and all others are just generic dioxin gas producing paper.

Make sure all hinges & covers are correctly on!

You may have a thermostat problem.

Contact a Bunn service center and have the unit checked.

This is usually the result of an incorrectly set timer (see p. 22 & p. 24 of manual) or stuck solenoid valve (p. 18). A link to the owner's manual is provided below. You should read the manual thoroughly before attempting adjustments & repairs.

http://www.bunn.com/pdfs/commercial/manuals/29251.0000.pdf

I hope this helps!

Remove the top panel and look for the yellow float, this controls the amount of water brewed, to adjust remove some of the washers on the float and test until you get the amount needed.

Yes, but you need the pre weighed grommets from bunn, if you remove the top panel on the machine you will see the brew tank, within that there will be brown plastic shaft with a yellowish cylinder on top of it. There might be 3 or 4 washers on top of that yellow piece, those are the weights, when the water fills the tank it pushes the float up and when it reaches the top it turns off the solenoid. You should be able to try it without the top on.

I own a bunn and my brother's business owns 2 of these. The rule of thumb as he was told by the salesman is 2 oz of coffee grinds per 48 oz of water.