Friday, March 9, 2018

Fixing the heating, upgrading to a Nest

My wonderful homeland had a huge dump of snow last week, and then a fast thaw over the weekend, leading to all sorts of shenanigans, mainly involving burst pipes and the like. It's eye-opening to see what living without water is like, even for a few hours - no flushing loo, no washing clothes or utensils, no shower - it's like living in the stone age, or some blighted third world location. It certainly makes you realise how horrific it must be to live somewhere that's had decent utilities (power, water, internet) and then have it taken away from you. My heart goes out to everyone living in that situation.

Another side effect of the weather was a slew of issues with our central heating at home. Due to some leaks and a bad expansion valve, our heating system is incredibly temperamental at the best of times - the pressure drops to zero, I have to add water to get the pump working, then the pressure goes up and the safety valve kicks in, unless I nurse it very carefully.

A Very Old Thermostat

The cold snap meant we needed the heating on pretty much constantly, which has evidently put strain on all the components, culminating in our wall thermostat giving up the ghost. It was a Potterton PRT2, which is old enough that it's discontinued and marked obsolete pretty much everywhere - it doesn't even show up on the Potterton website, which is just awesome (and why the above link goes to a retail site).

It was functional (before) - it certainly isn't any more. For a few days, the temperature didn't remotely reflect the real world, and then finally it decided it was going to stay on "below" unless I turned it down to 5 degrees, and even then it kicked in every now and again.

This caused the pressure to spike, as the heating was on constantly, our house became comfortably warm, then ridiculously warm, and finally we'd had enough.

A New Thermostat

I've had a Gen 1 Nest Thermostat sitting in a box for ages, waiting to be fitted. I'd examined the instructions numerous times, but the Heat Link portion of the Nest was scaring me - inside the box were connections for 7 wires, and I understood four of them but was a bit vague on the other three. I had looked behind the Potterton thermostat previously, and seen that there were three wires going from the wall into the box, and that didn't appear to be enough wires to drive the Nest Heat Link. So, in the box it stayed (for more than a year).

After the PRT2 started to get flakey, I decided to order a pretty cheap replacement - nothing fancy, just a dial and a temperature gauge, as well as an indicator light showing if the boiler was expected to be working or not. With all the other issues in the heating system, having an indicator to show state is critical for debugging the system!

I settled on the Heatmiser DS1-L which was about £25 on Amazon. It arrived a couple of days later, the day after the PRT2 completely gave up the ghost. I took a quick read of the instructions, turned off the power, and got stuck in.

Off with the old, on with the new

Potterton PRT2 wiring

Here's the wiring inside the Potterton PRT2. Three wires coming from the boiler - Live (red), Neutral (blue) and Switched Live (yellow) - sometimes referred to as Call For Heat or Boiler Live.

You'll also see a tiny stretch of brown wire, bridging from the Live in terminal 4 to Common in terminal 2. For maximum correctness, the red wire really should be going into terminal 4, and then bridging to terminal 2 over the brown wire. I'll come back to this in a minute.

And here's the Heatmiser DS1-L with the same wires connected.

Heatmiser DS1-L wiring

The Heatmiser can work two ways - with 230+ Volt switching, or "Volt Free" switching. The former uses the live line to provide the switching signal, and the latter uses a different line (with a much lower voltage, e.g. 12 volts) to provide the switching signal, presumably with a relay or something to bridge the two. Because I've only got three wires, I went with the reasonable assumption that I should wire this thing in 230+ Volt mode, so I pinched the brown wire from the PRT2 and wired everything in as you see above.

Once the wires were done, I screwed it all together, turned the power on; et voila! a working, accurate, thermostat!

Heatmiser DS1-L

It was around this point (just after the radiators finally got warm) that a slow realisation dawned on me. The Nest Heat Link - that needed four wires, didn't it? but maybe it could work with three and a bridge wire.

And indeed, in the manual, there's a paragraph describing just that:

"If existing controls operate at mains voltage, you can add a jumper cable between live and common. The jumper cable should be 0.75mm2 and 55mm long (with 8mm of exposed cable at each end)."

I'd totally missed the relevance of this the first three or four times I read the installation instructions. Oh well! So, that meant I should be able to simply replace the thermostat with the Heat Link box. 

The first issue I came across was that the wiring holes for the nest are really small - barely large enough for the single-core copper in my heavy duty spare wire, and definitely not large enough to fit a jumper wire and the live wire into a single hole - so I crafted a single-to-double splitter with some spare wire and a cable connector, turned the power back off, and got to work for a second time.

Here's the wires all attached inside the Nest Heat Link. The thermostat wire (the right two connections) is some temporary cable I was using to check the whole shebang was functioning properly.

You can see Neutral (blue) in terminal N, one of the two Live wires in terminal L, the "Satisfied" terminal (1) is empty, the "Common" terminal (2) is the second Live wire, and the "Call For Heat" terminal (3) contains the yellow wire.

The remaining two terminals on the right are the 12v connection between the Heat Link box and the Thermostat puck. You can connect the two wirelessly, but if you do that you need to provide power to the Thermostat puck over a USB cable. I debated for a while as to where I actually want to put the Thermostat, and finally decided that the best place for it was probably where we had the PRT2 anyway. So, I ran a tiny portion of cable connecting the two boxes. The Thermostat puck has a backing device that has both a USB charging port and two terminals for the other end of the connecting wire. If it's wired to the Heat Link, it charges over that connection, so no USB connection is required.

I originally sited the puck on the provided mounting plate, but it looked a bit rubbish - I think having the circle of the thermostat is a much nicer look on the wall.

Fully Installed

Power on, and a bit of tidying up - and it works! It's great to be able to trust the temperature sensor, although we've been used to the old "18 degrees" which was probably closer to 22 or 23. I wish I'd sanity-checked the old thermostat temperature before it decided to die on us.

Is the Nest any good?

We've only had it running for a day or two now, but I really love how we can control the temperature overnight, when we're out of the house, and use the phone to adjust things. I also like the look of all the smarts in the system (true radiant, scheduling, that sort of thing). I don't have any other Nest products, so I don't know whether the ecosystem as a whole is worth diving in to - and I probably won't need anything other than this particular device. So far, though - two thumbs up from me.

Monday, February 5, 2018

Life, Liberty and the pursuit of Happiness

A whole year has flown by; or maybe it's fairer to say it's crawled, staggered and rushed by, depending. My intention of having a flow of work-related posts on my work site and personal posts on this blog right here just didn't come to pass, and I think it's time to remedy that.

I've had over a year now - nearly two years, in fact - of self employment and rumination time. I think I've learned more about myself in that time than in the previous decade, and it's an ongoing process.

The American Declaration of Independence contains a phrase stating that all men are created with some unalienable rights, among these the rights to Life, Liberty and the pursuit of Happiness. I've been lucky enough to really give that a go over the last year or so - or at least to try and identify, for me, what these things mean and where the value lies.

I can tell you one thing, right now - working sucks. Or, to be more precise (because it really is relevant) - working to enable subsistence sucks. Work, in it's many forms, is awesome. Creating things of value - turning time and effort (and occasionally raw materials) into useful constructs is a wonderful pass-time. Working to pay the mortgage - not so much. I really wish that every human alive had the opportunity to live such that their passion was their goal, regardless of the fiscal value associated with that effort. I've been able to spend the better part of a year pursuing my passions (VR development, scanning technologies, learning about cool things, as well as spending time with my family) and it's enriched me hugely. I wouldn't give that up for all the tea in China.

Can you imagine living in a society where people worked because they wanted to, rather than because it was required to prove their value to enable subsistence? Note, I don't say "to survive", because I think we're already in a place where we've moved past the basic necessity of everyone putting their daily effort into providing food and shelter for themselves, their family and their tribe. Try as we might (and the culture we live in tries *really hard*) we honestly don't need everyone to be slogging their guts out to feed and clothe themselves. We already over-produce food, there's no reason we couldn't over-produce housing if our society deemed it valuable. We certainly over-produce plastic crap and reality TV.

So, what are we all working for? What are we all working towards? Are we all working to provide ourselves with an identity? What's the point of it all?

I've just finished reading a very interesting deconstruction of Banks' Culture which touches on the basis of a non-resource constrained society, and the motivations for being part of it. I'd like to think that at some level, we've already solved the Life and the Liberty parts of the equation, and should really be starting to drill down into the Happiness bit. So much of this is tied up in our self and cultural identity, it's kind of scary envisioning where our society moves to when much of the "work" becomes unnecessary, and then irrelevant.  As autos replace taxis (which they can, and likely should) - what does that mean for those who use that role as their subsistence tokens and cultural identity? What happens as the other roles get taken away?

Are we still going to live in a society where, if you're not clocking in 40 hours a week, you are "part-time"? If you're not gainfully employed in some fashion, you're lazy or worth-less compared to those who are? If you haven't read Keynes' essay where he postulates a 15 hour working week, I'd highly recommend it. One key phrase: "We have been trained too long to strive and not to enjoy."

When people begin to divorce their own worth and identity from their societal role - who do they become?

I appreciate I'm regurgitating the thoughts of a well-regarded critical thinker from nearly a century ago, but I think the coming decade is going to bring an end to the expectation that there will still be meaningful "work" for every person to do, for the benefit and advancement of society. Indeed today, much of the work that people do is centered around diverting people from appreciating the time they do have to spend on themselves, and our society is heavily structured around reinforcing the self-value of striving (working) as self-worth.

I think we've solved the economic problem - maybe now's the time to solve the other matters, of greater and more important significance.

Sunday, February 28, 2016

Evryway dev blog is live!

After a hard week bashing away at the keyboard, I thought I'd get my first dev blog post up. I'll be moving pretty much all my technical posts over to Evryway from now on. Take a gander!

Friday, February 26, 2016

What a week!

This week, I have mostly been making a holodeck.

I've got motion tracking working with a mobile headset (Tango in a durovis Dive) including device input (Droidbox), gaze tracking, world-space menus and a bit more. From scratch. The Unity ecosystem that enables all of this stuff is simply incredible.

This morning I also received confirmation that I'm incorporated!

Videos to come shortly, but I'm really happy with progress so far.

Next week I'll be getting live environment capture into the device working, which I think is going to be pretty special - possibly something that no-one else has shown yet.

There's a huge amount of work ahead of me, but it's amazing what you can get done in one week, even with the distractions that come with working in your garage!

Tuesday, February 23, 2016

Rift confirmation

The Oculus kickstarter just asked me to confirm my address. Awesome sauce. It's coming!

Saturday, February 20, 2016

Good lord, this is scary

So, I'm sitting here.

ready to begin.

I have a *huge* number of plans for things to make and things to do. Enough for a lifetime.

Where do I start?

Step 1. Breathe.

Step 2. Start a new repo!

OK, that's step one done.

A new beginning!

I'm unemployed! woohoo!

Yesterday was my last day as a Zynga / NaturalMotion employee. Lots of mixed feelings - leaving behind the Boss Alien crew has been really hard, I get the feeling I'm going to be missed which is nice. No paycheck is going to be very hard to adjust to.

I'll not be sorry to see the back of the corporate environment. The way big companies make games is just - well, not ideal. I think I have enough information now to write a book on it. Whether anyone would listen is another matter entirely.

I'm incredibly proud of the work I've done over the last 4 and a bit years. We've made a lot of mistakes along the way but we've created a game that's spawned a franchise, has over 200 million downloads across the various platforms and incarnations so far, and I wouldn't be surprised to see that double over the franchise lifetime. We've been running a live game for over three years, which is just crazy.

I've had a large number of awesome times working with team Boss Alien. Given that I was involved in hiring a large majority of the folks I've worked with, I can safely say that our "only hire people who are competent that we like" policy and our "yes, maybe, no - and a maybe is a no" policy has worked out fantastically. Or maybe it's confirmation bias. Anyway, it was the best leaving card I've had ;)

So - what's next?

VR is next! a big steaming bucket of VR!

and the first thing I'm going to be working on is a holodeck.

And I'm going to try and document my progress, pretty much live.

If you're interested in watching or participating, drop me a mail. I'll be looking at ways to fund this over the next month or two - I've got a warchest that'll get me through summer but if I can figure out a revenue stream by then I'll be able to think a bit bigger. Patreon and Kickstarter are options, I guess.

I've got a lot of bills and logistics to get cracking on next, and I've got to recreate all of my hacking and prototyping of the last year or two, from scratch, starting today.

Time to get cracking!