I’ve had a tour of a newly refit church hall where the equipment isn’t entirely as expected, so there are questions about whether the system meets the requirements and is set up properly. There have been a few surprises along the way (there always are!). The main questions are, as always, all about the controls, but this time, with three possible issues – whether the centralized controls will play nicely with fan convectors that have individual controls, whether the users can do what they need and no more, and whether the heating management is simple enough for volunteers to work.
Going back a few years before HeatHack, when we thought the main goal was saving energy, we were looking at lighting as well heating – and I had a pleasant experience revisiting those times this week, when Christ Church Morningside reminded me that they’d recently completed their lighting refit.
I wasn’t very involved in the latest changes, but I did do quite a bit of head-scratching in the early days about what lamps went in what fittings, and why. When I first looked, the main floor of the building had 89 light bulbs of 17 different types and was drawing just under 10 kW of power during services when they were all on. St John’s, on the other hand, had it easy with every lamp identical. In maintenance terms, that made a lot of sense, but wasn’t going to work in this place without chandeliers. Yes there’s the energy costs (financial and externalized), but what I learned for high level systems is that maintenance costs and health and safety are even more immediate reasons to get LEDs in. Scaffolding for this site is £1000 a pop, and you don’t want anyone tempted to go up high ladders because yet another halogen has gone out!
They’ve got their systems sorted now, so it gave me great pleasure to once again sort through the lamps, this time for looking at what could now go. That’s a whole black bin bag ready for disposal.
I’m getting a good trickle of HeatHack-related coffees and emails coming through – this week’s highlight looks to be before-and-after radiator measures – but I’m still having to take things a bit slow with some outages I can’t always predict ahead, so Tuesday nights are still off.
If there’s a particular session, with a particular focus, you’d like to have as a group before Christmas, do let me know and I’ll make sure that happens. Otherwise, I’m minded to just let the Tuesdays slide for a bit while we think about how best we can help the community. The demand is now there, and we have enough show-and-tell devices to grab attention while we explain ourselves. Most of what we have in mind now is site visits and looking at the data with people who know their buildings – not on Tuesday nights, though. Plus development of a few more things, some of which are because they’re helpful for the engineering (like the anemometry, and making the three-phase electric monitor easier to deploy) and some because they’re interesting and explain us a little deeper (like the thermal comfort game). Despite the current vogue for pair programming, that doesn’t fit the current model either.
As most of you know, I’m temporarily a bit unwell (although not as unwell as my laptop – time for a change!). I’ve decided that rather than try to soldier through, I’m just going to cancel the October sessions. That way at least you have advanced warning for the one that’s not today! Apologies, and we’ll see how it goes after that. I am up, though, for coffee or similar with anyone (new or old) who wants to talk or explore a building.
When I updated the SD cards to include heathackhub as a service (so that the pis would survive rebooting), I did it using the May 2016 Raspbian Jessie Lite, our first time with Jessie, I think. (“Lite” just means for headless and that doesn’t really matter here – it’s just smaller and more appropriate to how we deploy.) Unfortunately, I hadn’t realized that the Edimax EW-7811UN dongles we have don’t work with it, at least for us, but also for many other users.
Continue reading what’s up with the wifi
– and I think what I’ll do is bring along that phone/tablet app for us to look at, since at one point a good few people were interested in how that technology works. It’s really two apps – a really basic one for checking the internal weather conditions in a venue, and a little game about thermal comfort. I’ll need to remember the basics myself, but there’s always Google!
7:30 City of Edinburgh Methodist, in the basement –
Something about the building works at Christ Church tripped out their heating timeswitch and did a factory reset on it. I’m guessing there’s an internal battery that’s dead, as it’s relatively old. Unfortunately, it’s also a domestic model – and the defaults are for heating morning and evening. That’s a lot of gas to no effect – something we definitely want to avoid!
Continue reading …which reminds me, alerts –
… but the cycling round will take a little longer, I think. As will figuring out what level of my notebooks to transfer on line (and where) for the Cambridge-based folk; I aim to remove the guff from when I was still learning and making what I know available, but it’s the how!
With apologies, I’m unwell, and I won’t be able to make it out. On the other hand, I am working on getting the SD cards set up with the upgraded Pi image so that our setups can handle being power-cycled.
And I’m also having Tim’s code teach me how services work, so I can make the same kind of set-up for our second image – the one for monitoring electricity usage (helpful for debugging the random spikes and high periods one gets in community buildings!) whether it’s one or three phase.
While Christ Church Morningside’s hall is being refurbished, their Centre has a very different use pattern from usual, and we want to make sure everyone is well served. It’s a modern building with a nice big sunny window, but autumn is coming! Here’s the graph for it. This is actually the first time we’ve fielded a pi with the version of the webserver that restarts automatically when the power is cut – the documentation and process all works well, but if you update elsewhere in the field, be sure to leave enough time to make the required updates to the existing software (largely, npm packages).