Product Experience Journal -Thermostat (01/16/23)
I already feel glad that I could have come this far, my second journal, to keep my new year’s resolution. I will look into a very common product in everyone’s daily life, thermostat as your home heating system.
Preface
As a mover/shaker, I travel quite often and move frequently as well. Either at someone’s place or my new place, first thing that I have to deal with is a new thermostat controller. It’s a shame that I haven’t seen a thermostat which feels easy enough to use. Often times I give up on using it and jump into bed and shiver. I will hash over user experience problems from a few instances and propose solutions.
Product Experience Problems
For this product analysis, I will reference three(3) of criteria from Usability Heuristics to gauge product problems (Thanks to Nielson Norman Group). Plus, one more quality that I want to highlight.
I strongly recommend Nielson Norman Group Website to delve into usability issues further.
Heuristics Analysis Problem
(1) Visibility of system status
(2) Consistency and standards
(3) Flexibility and efficiency of use
Other problem
(4) Highlight on primary action
(1) Visibility of system status
Visibility of system status is about whether an user interface explicitly tells which stage the user is at. By doing this, the user doesn’t need to remember what actions have been done so far. Ultimately, the user could focus on the task that he/she wants to do.
Let’s have a look at gmail interface above. There is a highlighter on the left side which shows what stage you are at (inbox?, sent? or archive? etc). Imagine that we don’t have this side bar. You wouldn’t be 100% sure whether the mails you see now are the mails you have received or you have sent till you look into those closely.
System Visibility helps the users become more productive and efficient. Let’s see below to check the visibility of the thermostat.
It clearly shows if the system is on or off. However unfortunately, it doesn’t show explicitly which temperature you are adjusting. (You might wonder what I meant by ‘which temperature’. Interestingly, the heating system lets the user control hot water temperature as well as the room temperature. So the system should indicate which of the two are now controlled but it doesn’t.)
Let’s see another thermostat having one control only.
It shows which system you are at straightforward by having the physical indicator (cool-off-heat).
But sadly, it has its own issue.
The user needs to hold the arrow button for a few seconds to change the temperature. Then the blue light is on and then the user finally can change the temperature. In terms of visibility, it’s fine but you would never know till you accidentally hold it for a few seconds. Otherwise, you will never make it. The number you see before this point means the current temperature. (Who the hell would know that the number without blue light is just current temperature)
(2) Consistency and Standards
The consistency in a system or in a product group lessens the cognitive load of users.
The thermostat above has two different temperature control environments. For room heating, the temperature goes up and down by arrows while the water temperature changes by the single button. As the user hits the button, the temperature loops around “temp1->temp2->temp3->temp1->…”.
The user needs to learn new things since the system doesn’t keep the consistency in control.
(3) Flexibility and efficiency of use
For most products — I want to say, for any product — products need to consider at least two different use cases. One is an advanced use case and the other one is a basic use case. It might sound quite vague. Let’s see the brief definition of each
- Advanced use case : A user already gets used to the system. So he/she could do complex tasks, such as setting a timer, fine-tune of water temperature and room heating temperature.
- Basic use case : A user is new to the product or too busy to do complex tasks. So what the user wants is “doing the main job”. Here, it will be “making my space warmer” or “stop heating my space”.
Sadly, so far I haven’t seen a thermostat doing this job properly.
(4) Highlight on primary action
If I could go one step further. I want to add final touch — primary and secondary action.
What would be the user journey of product? or what action would the user care more? This is a critical question that designers should answer. And of course the design should align with this story by emphasizing it visually.
We often see buttons like above. Expected primary action has bolder visual than secondary action. It draws attention and guides the user to the intended action. It is not a deal breaker though, it certainly helps the user.
Product Design Proposal
With all the observations in mind, I want to propose prototypes.
One for without timer — I don’t think ‘timer’ is commonly used. I sometimes see products with timer though, I haven’t seen, at least those around me, users who appreciate its timer function — and the other one is with ‘timer’.
Let’s see the product I think desirable.
- Product without timer
The product has three(3) states. This product has minimum keys for its essential activities. When the user hits the power button, it loops three different phases. (On->Stand by-> Off)
The old fashion mercury thermometer indicates the current temperature with flame symbol(indicates it’s actively heating) and the temperature being set up.
When the state is either ‘stand by’ — when you go out but don’t want to get freezing damage- or ‘off’, corresponding symbols are indicated.
- Stand by or go out : Door icon
- On : Power Icon green
- Off: All icon dimmed off
I personally don’t think even the ‘stand by’ is necessary. But there are some regions which counts on water-piped heating.Shutting completely down might cause pipe bursting.
- Product with Timer
Since the timer isn’t a primary action nor secondary action, I put the dial controller separately. I often witness a multi-layered information architecture (See Fig 10.) discourage users to explore it’s functionalities. When a feature/menu is deeply nested in a system, user’s journey to get there is inevitably complicated and it easily discourage many use cases.
#1 Default state
As a default state, it shows the same screen as before
#2 Time change state
Once the user rolls the timer, the screen shows the timer option with guidance text: “in ## hours/minute, off”.
#3 Screen with timer
Once the user confirms with push the dial, the main screen shows timer
#4 Infinite/default state
If the user rolls the dial fast and long, it turns the system back to infinite timer state (don’t turn the heater off)
Epilogue
I didn’t include hot water controller since I really don’t think that’s the feature that most users need. Plus, I deliberately didn’t design a fancy touch-screen product, hoping it would be more accessible to broader audience. The heating is the most basic stuff that anyone could control easily even if you aren’t a digital savvy.
Overall, for this post I tried to include a little bit of professional knowledge and theory to make it a bit more informative and helpful to those who are interested in product design industry. I hope this post to be interesting enough as well as informative.
Did you find it compelling? Check out the previous series (seat controller) or Introduction.
The next series is about digital watches (hit the link to see the next one).
