Can I overclock my tea kettle?

April 3, 2009 12:10 PM

It seems like my tea kettle (on a gas burner) boils more quickly when there's a large volume of water in it than if there's just a bit. Am I imagining this, or is there a reason it might happen?
posted by Mayor Curley to food & drink (15 comments total)

1. Time it.
2. Come back and ask again if it turns out to be the case.

A watched pot never boils, of course. So perhaps you watched the large volume for longer...
posted by le morte de bea arthur at 12:18 PM on April 3

You're imagining it. There's absolutely no reason why your impression might be valid; provided that you're using the same equipment and the same setting on the burner, the water will boil faster with a smaller quantity of water.
posted by Simon Barclay at 12:29 PM on April 3

Water is contacting more of the hot surface of the pot because it is higher up the sides. More contact means more heat transfer.
posted by Pollomacho at 12:30 PM on April 3

I would guess it's a function of pressure. When there is little water in the kettle, it takes a long time for the pressure inside the kettle to build. When there is a lot of water, it takes relatively little time for the air to heat up (since there's less volume of air) and create pressure.
posted by Night_owl at 12:30 PM on April 3 [1 favorite has favorites]

Oh, and you can't overclock boiling anything unless you restrict the steam from expanding.
posted by Pollomacho at 12:31 PM on April 3

Are you judging based on how long it takes the kettle to whistle? It takes a certain volume of steam being produced fast enough to make it whistle. When you have a lot of water, you only need it to be at a slow boil to produce enough steam fast enough to make the kettle whistle. If there's just a little water, it would need to be boiling like crazy to get a good whistle, which takes longer.

That, however, is just wild speculation - seconding test it again, being careful to use the same setting on the stove etc. My strongest suspicion is that it's just perception, and the small volume does indeed boil faster.
posted by pocams at 12:37 PM on April 3

Pollomacho has it backwards. With more water there is more volume and a lower surface-to-volume ratio. So the time it takes to boil water in a kettle increases more than linearly as you add water. At least, that's my experience.

So yes, you're imagining it.
posted by alms at 12:37 PM on April 3

In university I had a crappy electric range that couldn't boil a kettle anytime today unless it was nearly full. It took that much weight for the bottom of the kettle to make half decent contact with the warped coils..

Just out of curiosity... you wouldn't happen to be putting warm water from the tap in your kettle would you? It might also be that the temperature of the water is higher by the time you fill the kettle.
posted by mce at 12:40 PM on April 3

Check the warped coil issue, and check the boiling v. whistling issue, then clarify your claim.
posted by craven_morhead at 12:57 PM on April 3

I was just basing it on the whistling. It's not heating faster, it's just whistling more quickly. Thanks for the answers everyone. I'm a little less stupid now than I was an hour ago.
posted by Mayor Curley at 12:58 PM on April 3

If you want a kettle to boil faster, get an amazing electric kettle. Just a suggestion since I adore mine.
posted by scazza at 1:25 PM on April 3

Seconding perception. A larger mass of water will require more energy to convert it to steam. It will produce more steam and is likely to be more efficient since volume to free surface ratio is higher but it will take longer to produce steam at the same energy input rate.

BTW it still suprises me thnat electric kettles are so rare in the states. In the UK they are a given in every kitchen. Isnt it a real hassle every time you want some hot water?
posted by BadMiker at 4:51 PM on April 3

BTW it still suprises me thnat electric kettles are so rare in the states. . . . Isnt it a real hassle every time you want some hot water?

Cup. Water. Microwave.
Who needs another kitchen gadget?
posted by D.C. at 7:50 PM on April 3

Agreeing with D.C. — boiling water in the microwave is the way it's done. (You people still boil your water on a stove?) :-p
posted by exphysicist345 at 9:06 PM on April 3

(You people still boil your water on a stove?) :-p

electric kettles aren't on stoves; they sit on a countertop and are plugged in, and their only purpose is heating water. You fill with cold water, turn on, wait a minute, ding, hot water. Easy for french press coffee and tea which I find are more popular in the UK, whereas in the US we have more drip coffee makers for coffee (which heat the cold water the same way as electric kettles but then only produce coffee), and we don't make much tea so microwaves suffice for the occasional cup.
posted by mdn at 11:45 AM on April 6