Temperature Indicator for the Faucet




About: Innovative Projects, Diy's, Life Hacks

In some houses you might find that it takes ages for the hot water to reach the tap.

My bathroom's tap is the worst.

I need to open the tap almost to the maximum to turn on the gas water heater and then wait for a while for the hot water to arrive.

(Yes it's a waste of water, I know!)

So, when I want to fill the bath for my son, I have to keep checking the water to know when it's getting warm.

It would be much easier if I could see it from the distance, that way I could do something useful while the water is heating up.

You can buy LED faucet nozzles with a temperature sensor or you can make your own temperature indicator without using LED's or batteries.

In this Instructable, we'll look at a way to make a battery-less temperature indicator for the tap.

What's needed:

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Step 1:

I already had thermochromic pigment and nail polish mixture left from another project, so I did not need to mix it this time.

Step 2:

Take off the nozzle/aerator and cover the parts you don't want to paint.

Spray-paint it dark red.

I tried 2 different shades of red and in my opinion the dark red looks better.

Step 3:

Make sure the paint is dry before proceeding with the next step.

Paint the nozzle blue with the nail polish.

That's it!

Step 4:

We have made a temperature sensor (kind of)

When the tap is closed or the cold water is running, the nozzle will stay blue.

When the hot water starts to heat up the nozzle, it will change the colour to red-ish.

Now you can brush your teeth while keeping an eye on the running water.



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    7 Discussions


    3 years ago

    Cool!! You should really enter the "home hacks" contest!!


    3 years ago

    A great idea. how much pigment did you add to the bottle of clear nail polish?

    1 reply

    Reply 3 years ago

    I did not measure it.

    I kept adding it bit by bit until the nail polish looked blue enough :)



    3 years ago

    Amazing! I guess you could also fit one of those "mood rings" around the nozzle to reach a similar result

    1 reply

    3 years ago

    This is a smart idea! I need it because my mouth guard requires warming under hot water before I put it in, and the hot water sometimes takes a while to start.