Are mug warmers safe?

August 14, 2022 3:24 AM

I want to buy mug warmers to keep on my bedside table and desk to keep my drinks warm but I am worried about safety, given that I am super forgetful (hence cold tea) and have a lot of cats around. How hot do these get? If a pillow fell on top of one, would it catch fire? Would the cat??
posted by dorothyisunderwood to Shopping (13 answers total)

Not likely. If the non-regulated temperature stayed above 212F / 100C your cup of beverage would be boiling and evaporate. Paper burns at 451F. There's not much that will catch fire and burn at what would be boiling temperature from a mug warmer that isn't an electrical fault or something. Let's not go into the ignition temperature of cats, probably hotter than paper....

There are immersion heaters that quickly re-heat some mug of something quickly and are removed that could be designed to be hot. But the on your desk keep your mug warm isn't going to be even designed to reach boiling water temperature. So the temp is going to be less that 212F/100C and that's sorta the max. Don't stick your hand in boiling water, duh but it's not going to burn down your house because it's hot.

It's probably more likely to be not hot enough.
posted by zengargoyle at 4:37 AM on August 14, 2022

How long do you forget your tea for? If it’s only like a half hour, you may want to try a different mug. I have an Edgecomb Potters whale tail mug that keeps thing warmer longer due to the shape. And it’s not just a placebo effect; conical mugs keep beverages warmer for longer.
posted by donut_princess at 5:41 AM on August 14, 2022

A quick search shows that most mug warmers don't go above 150 F. One went up to 167 and surprised the reviewers, but that's on its highest setting (it has 3). *HOWEVER*, the heating element themselves may go above that.

The cat wouldn't like it, but instinct should tell it to stay away.

Generally speaking, it's better to brew a little tea at a time than brew a lot of tea and have it go cold. But then, I'm talking more about Chinese tea brewing than British/European tea brewing. A tea spoon of tea would be enough to brew all you can drink all day, and probably the next day or two. Maybe have a hot water dispenser instead of a warmer?
posted by kschang at 5:43 AM on August 14, 2022

I used a mug warmer for years at my desk, and I never felt worried about having books or paper near it. They get warm, but not hot. This is assuming you're referring to the kind that also double as candle warmers, though.

However, I finally got tired of having yet another thing on my desk so for the last few years I've been using an insulated mug, specifically a Klean Kanteen Insulated 16oz Tumbler, but there are a lot of choices available.

That keeps my tea hot to warm for a few hours, and by the time my tea actually gets tepid that's my mental signal to get up from my desk and move around a bit.
posted by ralan at 5:58 AM on August 14, 2022

My co-worker swears by her Ember mug. She likes her so much, she started giving them as gifts. Pricey, but maybe it's your holy grail. (See what I did there?)
posted by XtineHutch at 6:11 AM on August 14, 2022

(If the idea of a more passive approach to keeping your tea warm interests you but you don’t like travel mugs, do a search for “tea mug with lid”, where you’ll find a variety of other options that are like a regular mug, just with a fitted ceramic plate/lid that fits in top to help keep heat from escaping.)
posted by eviemath at 6:30 AM on August 14, 2022

I also am a tea drinker and forgetful and with cat. I use an insulated mug with lid and handle. I have the type with a wider base, not the type that fits in a cup holder, because those are too tippy for me (and the cat). Here is an example of the type I am talking about. Here is another one. My current favorite.
posted by gudrun at 6:51 AM on August 14, 2022

🚨🚨 Incoming anecdata 🚨🚨

One of my friends has a painting and papermaking studio in her basement, and she has a few mug warmers around for keeping liquids warm (gelatin and beeswax, off the top of my head). Anyway, hers are covered in spatters of paint and are surrounded by paper and particles and all sorts of scatterbrained artist detritus that have piled up over the years.

I'm not saying it's a OSHA approved land of safety, but I can verify that some artists find them handy for keeping small amounts of liquid stuff warm.
posted by Gray Duck at 6:52 AM on August 14, 2022

I have a mug warmer that only turns on when you put something on top (it needs to push down). I’ve had zero problems, but my spouse recently melted some computer components, which…. Why would you put it on a mug warmer?

Tdlr: love my mug warmer, but hard if you share a desk.
posted by Valancy Rachel at 7:28 AM on August 14, 2022

Plug it into an automatic shut-off timer and never worry about forgetting to turn it off.
posted by qxntpqbbbqxl at 9:53 AM on August 14, 2022

You can get induction mug warmers that don't have heating elements, like this one I use. The base is only activated when you set the mug on it (there's a gravity button that the mug rim triggers) and even when warming, the base does not heat up. You have to use that specific mug with it, but it's a pretty good ceramic mug with a nice lid; I like it. It doesn't hold a tanker's worth of coffee, but I consider that a good thing, as getting up for more coffee keeps me from sitting at my desk until I turn to stone.

I specifically got this instead of the Ember mug because Ember mugs don't warm your hands - the mug stays neutral-to-cool even when the liquid inside them is hot. I wanted a mug that would actually feel warm when I cradle it in my ice-cold hands at my desk in our brutal New England winters, and this fit the bill.

Bonus, when I'm not warming my coffee with it, I can charge my phone on the pad.
posted by invincible summer at 12:26 PM on August 14, 2022

I've had this inexpensive mug warmer for about 8 years now, and despite my clumsy and forgetful nature, it's never caused me any harm. Just this week I inadvertently left it turned on with an empty-but-for-the-dregs mug on it from Thursday morning until Saturday morning, and while the bottom of the mug was hot, the mug itself was fine and nothing caught fire or broke. I've also accidentally touched the hot plate on occasion, and while that'll certainly get your attention, it's not instantly damaging so I suspect your cat would be fine. Despite this, I find that it keeps my coffee suitably warm all morning.

I've never knocked a pillow onto mine, but I truly do not think it could catch one on fire.
posted by DingoMutt at 9:32 PM on August 14, 2022

I ended up splurging on a S'ip by S'well insulated mug and have been extremely happy with it as (pointed out above by several) I can carry it around without having to plug and unplug a warmer. None of the mug warmers recommended above were easy to get locally, and the knock-offs all looked a bit dodgey to me.
posted by dorothyisunderwood at 2:16 AM on September 14, 2022