Author Topic: Moteino Coffee Maker  (Read 35043 times)

LazyGlen

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Re: Moteino Coffee Maker
« Reply #15 on: January 08, 2014, 02:50:05 PM »
Thanks for checking, I'm glad you could corroborate what I saw.

As far as brew temps go, after the stoopidity with McDonalds coffee years ago, I'm guessing that they went for (good_enough && No_Burns) over (ideal_brewing_temp). I will rig up a safer than 'lean it in the kitchen sink, plug it in and don't touch' test location when I get to messing with it again.

I hope I didn't interfere with your caffeine intake too much!

LG

dr_barger

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Moteino Coffee Maker
« Reply #16 on: December 08, 2019, 02:08:25 PM »
I know this is an old post, but I've searched for the Keurig's low water temperature issue and haven't found anyone that's posted a solution.

The first cup in the morning may only be 155 degrees in the cup due to heat loss from the myriad of hoses, fittings, and nozzles inside the maker. I added a resistor in-line with the temperature sensor on the water heater boiler tank. This causes the temperature controller to interpret the signal as a lower temperature.

As you mentioned above, the temperature sensor is a thermistor that is attached to the side of the water tank by a stainless steel band. I cut one of the leads to the thermistor and soldered wires to extend it to the base of the coffee maker. This allows you to attach different value resistors to the wires and test without having to disassemble the maker each time. I also added a toggle switch to bypass the resistor which returns the water temperature regulation to its standard setting.

I settled on a resistor value of 680 ohms which increased the Keurig's water temperature by almost 20 degrees F. The larger the resistor's value, the higher the water temperature. If you put in too large of a resistor, the effective setpoint may be greater than the water's boiling point and the heater will run continuously.

Don