Usability aspects of gas cookers
In this first article of the “power-off” series, I shed light on how we interact with low-tech equipment — in this case, a kitchen stove. Considering that this device has only five knobs and no electronics, it exhibits some surprising usability problems!
It’s Friday today, and since everybody likes to slow down and take a step back from their work on Fridays, I will designate Friday to be the power-off day in the Yes/No/Cancel magazine. It’s the day to switch off the computer and look at things beyond it. As a computing professional, you occasionally forget about the real world around you!
(Ironically, I’m still using my computer to write this article and you are using yours to read it. So it’s hardly sticking to the spirit of “power-off”… but how about this: If you want to really go for the whole non-electronic experience, give me your address and I’ll post you the power-off article every Friday. Yes, on paper. How about that? Shocking, eh?)
Today’s topic is the gas cooker at my home in Cambridge. And no, that’s not such a lame topic as you may think. This is a device which I interact with pretty much every day, and it is therefore important that I feel comfortable using it.
Here is a photo of it — click it for a larger picture. (I specially cleaned the cooker for this photo!) Very simple device: four hobs, one knob to control each of them, and a button to trigger an electric spark which ignites the gas. What could possibly be wrong with it?
My main problem with this cooker is that I never know which of the four knobs controls which of the hobs. Ok, the front two knobs are for the front two hobs and the rear two knobs are for the rear two hobs. But amongst these, which is which?
The only way of knowing is to look at the tiny diagram beside each knob. And the diagram is inconveniently placed such that it is hidden behind the knob if you are standing in front of the cooker! You therefore have to lean over in order to see the label. I generally cannot be bothered to do this, so I just try one of the two possibilities at random. And I generally get it wrong. And I get annoyed with the cooker. Call me lazy, call me a slow learner, the end effect is still that I’m annoyed. (Hey, I cook for myself from basic ingredients, I can’t be that lazy.)
The solution would be to arrange the knobs in such a fashion that it is immediately clear which one controls which of the hobs. The easiest way of doing that is to arrange them in a square, rather than in a straight line; however that might be impractical as the cooker would have to be wider. So this is my suggestion, an arrangement which is unambiguous but requires hardly any additional space:
(Comments on whether it is more aesthetically pleasing are welcome.)
I’ve not finished yet. The next thing I want to mention is a bizarre feature which seems to be common to gas cookers. (I grew up with electric cookers, so this is a bit new to me.) Here is a picture of one of the knobs. The arrow points to the right, which is its “off” setting. To turn on the gas, you turn the knob anticlockwise. Two things I find bizarre:
- In all other devices I can think of, turning the knob as far as possible anticlockwise turns it off (the “leftmost” position). Here you need to go as far as possible clockwise.
- When you gradually turn the knob away from the “off” position, you suddenly get the maximum flow of gas; then as you turn it further, it gradually decreases again. The small flame is furthest away from the “off” position, not closest as you may expect.
I’d be grateful for any explanation of why gas cookers work this way. My hypothesis had been that it’s good to get a strong flow of gas first thing after turning on, so that the spark will cause it to ignite quickly. Only today when taking the photo did I notice the little spark symbol next to the little flame. This suggests that you’re actually supposed to turn the knob all the way round to the little flame for ignition — that completely messes up my theory. Any other ideas?
I must say though, the strange behaviour of the knob doesn’t irritate me, as I’ve got used to that. The arrangement of the knobs does though. And in two weeks I’ll be moving house, so I’m going to have to start all over again getting to know my cooker.
You are not alone with the mysteries of gas cooking developement Martin. We just bought a Cannon (traditional C60GTX) a pretty pricey item. On this cooker you cannot read which knob serves which burner unless you stand three feet away because the legend is under and obscured by the respective knob. You discover by elimination and various pops which knob operates the burner on which the kettle has been put. We also discovered that the burner control was negligeable. When the knob position indicates that the burner should be at 50% the burner is full on, turning the knob to full power position has no effect whatever. What control there is takes place over about 8mm of the control knob. The Cannon service engineer told us that ‘it’s a general complaint, the burners are either on or off’. So much for progress. incidentaly the engineer was called because a fan which we didn’t know existed in this new cooker started to work for the first time after using the cooker for three weeks. Aparently the fan, which is very noisy, is bent and needs to be replaced. We are now deciding if we want this cooker at all.
Michael.
Comment by Michael Timberlake — Tuesday, 31 July 2007, 21:54 GMT
“I’d be grateful for any explanation of why gas cookers work this way.”
for a successful light you want the gas to be all the way on. Once the gas is on, you don’t want it to go out. If you put it on too low it can get blown out too easily, hence to use the gas you turn it past the on position and to a side where the minimum amount of gas is hard coded.
Also the biggest feature of usability, is consistency. That is how all gas knobs worked, get used to one and you can use them all. maybe you would like your gas knob to turn the other way because you’ve never learned how to use gas knobs - but once you do you expect that. Got to be consistent.
Comment by Dave B — Wednesday, 10 October 2007, 00:59 GMT
Once you get used to gas you will never want to go back to electric. After all the gas is immediate, it comes on, it can be adjusted instantly while viewing and can be turned off instantly. Electric takes time to heat up and adjustment is a guess.
Anyhow I have encountered a problem with my cooker. I have a traditional free-standing Cannon (Model 152) with a bonus Grill/Rotisserie ie a spit to roast a chicken or leg of lamb. Fabulous piece of kit circa late seventies. Everything works including hob burners but the oven has packed up and I am on the look out for the possibility of someone having had the same problem on same cooker who might be able to help. To buy the equivalent cooker today if it existed would cost a small fortune.
Comment by John Pasmore — Monday, 3 December 2007, 16:56 GMT
Hi,
You should rember that the gas controls on a gas cooker are taps,and like all taps have to be turned clockwise to shut off off the flow, think of screwing something in.
With everthing else, I agree that turning something clockwise increases whatever you are controling,however you soon get used to the idea.
Also, the taps are not like ordinary valves,they have pre-calibrated ports,which may make precise adjustment difficult,this is used to ensure that when you turn the gas down,you dont inadvertently shut it off altogether.
Comment by r simmonds — Sunday, 23 December 2007, 06:53 GMT
We have a Cannon Chichester Traditional 600 freestanding cooker, not a cheap item at just under £700. There is a design fault with the cooker, whereby due to the pan supports being a little too low, the gas flames on the rings are starved of air & often blow out. The solution to the problem is to raise the pan supports by just 4mm (by putting nuts under each corner as spacers0. Unfortunately these spacers cannot be left in position as the glass lid will not close with them in place. We have contacted Cannon about the problem, an engineer stated this is quite common, but he doesn’t have practical solution. Indesit (Cannon) customer service refuse to answer any e-mails, so letter was sent, the reply was an absolute load of patronising crap. The person even suggested the problem should be taken up with, and I quote “the Kitchen Company that recommended the product”. This so called customer service person obviously didn’t even read our letter, which stated the cooker had been purchased by us direct from Comet. If anyone else has one of these cookers, please be aware that using pans of the diameter recommended by Cannon will cause problems & remember if the flame is extinguished, the gas still flows.
Comment by R Hunt — Wednesday, 12 March 2008, 10:14 GMT
I have a Cannon Strafford and although the top and grill are fine, I have had nothing but problems with the oven.
Had an engineer out twice in the first 6 months to same problem who blamed the fault on Cookers not being made in england anymore only in europe and they have to be adjusted to work over here and obviously mine was not adjusted properly. The oven still does not heat properly and I am fed up with silly excuses.
Really fed up - obviously cookers are really expensive, so cannot change one just like that. I thought that by buying a good brand CANNON everything would be alright. I would have been better off getting a cheap one.
Comment by Jan Gillies — Tuesday, 24 June 2008, 11:03 GMT
Hello,
I start with much greetings to your company. My name is Garry Woodson from Chats & Co ltd Co. I found your add on web and am contacting you regarding some gas cookers am looking to order. I will be glad in doing business with you if you could get back to me with the types or your website if you do carry gas cookers so that I can browse through the type am looking for.
Regards,
Garry Woodson
Comment by GARRY WOODSON — Saturday, 19 July 2008, 18:13 GMT
Does anyone know of a gas cooker with fold down glass lid which does not require an electricity supply to ignite it? I recently bought one from zanussi, but it is a load of rubbish, and I am unable to have an electric socket installed near the cooker.
Comment by Sheila James — Friday, 12 September 2008, 15:00 GMT