Turn an Old Coffee Maker Into an On-demand Water Heater (nevermind)





Introduction: Turn an Old Coffee Maker Into an On-demand Water Heater (nevermind)

Joby Transform It! Challenge

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Joby Transform It! Challenge

Update:  Nevermind this one.  Too many electrical shock risks to make it advisable even as an experiment.

Hey guys, this was a fun and novel idea I had but on retrospect, I don't think it's really something safe enough to recommend for people to try for realz, so I am deleting it...

Thank you for reading!

Step 1: Are You Forgetting Something?

Did you read all the safety warnings and follow them?

Are you sure you want to do this?

Did you feed the cat? 


Step 2: Bathtime

Fill up the tub as usual. 

The initial water temperature of the bath was 96 degrees.

Step 3: Enjoy a Long Soak

Read a book or watch all the Sketchup tutorial videos from the comfort of your nice warm bathtub.


Step 4: How Effective Is It?

Thank you and stay safe.




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    I actually made a homemade water heater using a coffee maker and some other supplies. I travel in a motor home and do not like using LP gas so I ripped out the gas heater and built a rather cheap but efficient water heater. All in all, I spent maybe $60 to build and took a day to construct. I made a supply list and step-by-step instructions but it's not letting me add photos. I made a 20 gallon tank and it takes about 6 to 8 hours to get around 110-130 degrees. The only problem I have had with it so far is if I use well water, I have to clean the water lines once a month as lime and calcium build up. I use vinegar to clean lines.

    Awesome, good to hear that this idea can actually work. I got so much flack for this one that I deleted most of the article. Maybe you will post an instructable that people will appreciate.

    Used this years back to heat a hot soaking tub for my wife. You don't need a pump just put the coffeemaker at the water level of the tub and add a siphon hose to put the water back in the coffeemaker tank, that will make the two water level stay equal. Works great except the pot would calcium up after about 2 months of continual use and have to be replaced. I've since gone to a 5 gal bucket heater and a waterbed thermostat teaked a bit to raise the temp to 110 degrees.

    Interesting approach. Reminds me of a guy I know that used the heating element from an electric hot water heater heater to achieve the same thing.

    As far as I know he is still alive.

    Well this is disappointing. Heck, quite a few things here are a 'bad idea if you don't understand the risks'.

    Yeah, I tried to delete this one, but it was in a contest, so I couldn't

    What is the aproxima GPM output of hot water? Thanks. I was just wondering how long i am going to have to wait for a tub to be filled. I have a small 100L tub i want to fill for my camping expiditions. due to the girlfriend not wanting to camp unless she has hot showers/baths everyday. Thanks

    Can someone say sketchy? Haha, don't kill yourself with a coffee maker next to a bathtub.

    Damn, forgot to feed the cat.