Keurig B40/B60/B70 Automatic Water Filling System





Introduction: Keurig B40/B60/B70 Automatic Water Filling System

This is a simple project I did to avoid adding water into my machine each time I take a cup of coffee. It's a pretty simple system but it also requires basic plumbing knowledge and electrical / soldering skills :-). This DIY will work with B40/B60/B70 model or maybe other if you have enough place for the small bracket and water level sensor that we'll see in a moment. Note: some suggested in the comments a mini plastic float valve if its size fits your reservoir it might be a simpler setup (I did not test it).

Step 1: Ice Maker Maker Tap Valve Kit

First, get an ice maker self tap valve kit available in most hardware store for 8$-10$

Tap Valve Kit

For 3/8" to 1" O.D. tube
Valve with 1/4" O.D. comp. outlet
25'x 1/4" O.D. polyethylene tube
Compression inserts
1/4" O.D. comp. union
For installation of humidifiers, ice makers, and evaporative coolers

Step 2: Electrical Parts - Electric Solenoid Valve Water N/C 12V 1/4"

Next you'll need an Electric Solenoid Valve Water N/C 12V 1/4". It should be water type and "normally closed" to work with the system. I've got mine from Ebay for $12.50

Step 3: Electrical Parts - 12 Volt Relay

Next you'll need a SPST 12 volt relay. 6$ online

Or you can use one you have lying around.

Step 4: Electrical Parts - 12 1Amp + Power Supply

Next you'll need a 1 amp + 12 volt DC power supply. 6$ online

Or you can use one you have lying around. If it's 12 volt dc and 1 amp or more

Step 5: Electrical Parts - Water Level Liquid Sensor Float Switch

Next you'll need a Water Level Liquid Sensor Float Switch. 2$ online

Step 6: Plumbing / Water Line Installation

You will need to follow the included instructions to install the water valve. The idea here is to get the 1/4 water tube to the Electric Solenoid Valve then to the brewer water reservoir so you can control water flow through the solenoid.

Step 7: Electrical Parts - Installation

*WIRING for reference only. Relay pin 85 & 86 are the coil, and 87 & 30 are the switched contactor.

You'll need to wire the solenoid, the relay, the water level switch and the power supply so that the water level switch control the relay that activate the solenoid.

Step 8: Fix the Custom Bracket

You will need to make a custom bracket to hold the water line (hose) and the level switch. You can use a thin aluminum plate and then fix it to the reservoir.

Step 9: Enjoy!

Know you have a fully automatic Keurig B40/B60.

See demo video:



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26 Discussions

How is the fuse wired? What size fuse? And the what parts are needed?

nice trick...i'm still looking for a solution that doesn't fill the tank, but instead feed fresh water directly into the keurig on an as needed basis, so it never just sits in the tank

I think this was a great idea. I bought the same switch, and solenoid valve. The water pressure here is too high for a 2A power supply to open the valve so I got a 5A adapter and it works just fine. I also put a needle valve in line after the solenoid to turn down the flow to the water tank.

I drew up a bracket to 3D print to hold the float switch and water line, I'm new to Grabcad but I'll try posing a link here to download the STL. I'll try adding some pics of the finished project here too...

Bracket file link:

My next revision will add an extension to lower the float holder since this fills the water to the MAX.

Thanks for the instructable!!

bracket print.JPGbracket mounted.JPGlid closed.JPGvalve.JPG

Do you have any reason to worry about lead being present with the use of a brass water solenoid valve?

A good float valve walk through is here. Requires no extra electrical hook ups just water line plumbing. This method would work on ANY MODEL as long as the bulb isn't too big for the tank.

*the above is not my video so all questions please send him a message on youtube

1 reply

I've been planning on doing this so I thought I would look around and see what anyone else had done. I currently take the tank off the Keurig and fill it from the refrigerator door since that is filtered water. My wife can't handle the large tank so I try to keep it filled. She usually refills it with a large mug if I haven't done my job.

I had planned on finding a valve and float system similar to a toilet tank refill system. So far I haven't found one small enough to fit in the Keurig tank. I still prefer that although they are probably more prone to over filling and over flowing.

I may cave in and use the electric valve and float switch. Instead of the relay I would prefer to go to with an electronic switch. I'm an electrical engineer so that is right down my alley.

Like someone else mentioned it's also a good idea to implement a filter like the ones we use for refrigerator ice and water. It slows down hard water deposits building up in the Keurig.

Nice implementation!

3 replies

This is the float I used. It fits and works flawlessly, 2 years so far.

That's also a very good idea... But if space is limited the mini plastic float might be to big. If it fits in the reservoir, it's simpler of course. I've just ordered one to see on which Keurig it will fit.

I had a similar idea though I just used a really small float from Amazon. I will try this electronic method in my Lavica as it may not have room for the float.

hello, it's 40A relay cause I had it on hand. You could use a 5 to 10A without problem. There is even one person that suggested to go without a relay but I'm not sure that the little float switch would handle the load. I prefer a small relay. Thanks

K, thanks, i have one lying around, i got it from an old ups circuit. Its 12v 10A, (N.O).

Very nice. Plan to do something like this. Wonder if anyone has thoughts or experience regarding the use of this float switch instead:

It appears to be able to carry enough current to make the relay unnecessary.

2 replies

My system is about the same as SyCoQc (his switch bracket is pretty clever) but I used a stainless steel vertical float valve from Ebay (

drilled a hole in the cover) that is capable of carrying 0.5 ampere so the relay is not necessary and it prevents the relay chatter when the switch closes and the inrush to the valve lowers the voltage for an instant. I've been using my level control system for over 18 months happily as I hated hand filling each day. I've also installed it on my Saeco espresso machine. I would recommend installing a throttle valve on the 1/4 line so there is no vibration due to flow. Lastly, I have reverse osmosis water so using brass fittings is not permissible as the water will actually dissolve the zinc in the alloy resulting with leaks. My whole system cost $28 installed. I used to spend 90 seconds filling both machines so I save around 10 hours a year by automating, it was very satisfying. I wish I had thought of the bracket per SyCoQc to avoid drilling the cover.

The "Sensor Float Switch" I've used is rated at -> Maximum Switching Current: 0.5 A and Max Load Current: 1.0 A. So I think I could have done it without the relay but just wanted to be sure. About the bracket, yes it's a good idea because I'm now using a B70 Platinum model and I've simply swapped my little bracket onto the new reservoir. I'll also soon install a small overflow tube to prevent any spills because one time the float switch or something prevented to stop the water flow. I'll update my instructable. Thanks

Do you find that this system "stutters" a bit? The float sensor I bought seems to be a we bit touchy. Any ideas on making it a bit smoother?

2 replies

mine is smooth but I must add that I've set the tap valve to a very low water flow... If water level rise to fast the sensor assembly may stutter (if I remember a few test I did)