Saturday, December 20, 2008

DIY Zoning on Windows



Some of you may remember what I think of running mission critical applications on Windows (see above). However, not all agree, and for those who don't, there is a sister project now, running on Windows only:

HVAC Control System

Let me just say for the record that it I am very curious about how it turns out, and whether Windows can indeed sustain a mission critical application. In any case, hats off to Kevin.

Thursday, December 11, 2008

Tip Of The Iceberg: Security

Last place to find anything about climate control, I thought, would be the Schneier on Security blog. But then, when he posted about Remote-Controlled Thermostats, it didn't surprise me much - for this is the same idea that is deeply rooted inside DZ.

Of course, since DZ is not a commercial project, the full-fledged security framework is not there, just the reasonable initial framework.

But the point of this message is to emphasize that within every big problem there's a thousand small, trying to get out. Security is just one of multiple facets of DZ that is not on the surface.



For those interested, the original article is California Seeks Thermostat Control.

Still can't help but to ask myself how are they planning to control the legions of Honeywell mechanical thermostats, and who is going to pay for radio and Internet enablement of newer thermostats (last time I checked, Carrier Infinity was the only system that was somewhat enabled, and the cost is exorbitant). Have a nagging feeling that it'll be taken out of our pocket, but rest assured, in our best interest.

Wednesday, December 10, 2008

${mobile-device} + ${appliance}, Nokia edition

Not sure if this post reached the right audience, so reposting it here:

Nokia released the Control Center - a complete home automation solution.

Here's a video - there's a couple of fragments worth looking at if you're interested in temperature zoning.

I don't have any doubts that this system will be beyond the reach of the majority of readers here, and doubt that partial solutions will be offered (though wouldn't be surprised if this actually happens, I've been trying to show for years that this is quite doable).

Still, it's worth noticing that the big players are finally catching up to the game.

Thursday, November 27, 2008

Wednesday, November 19, 2008

Pulse, Reloaded

Once upon a time, there was an overheating video card. It begat the Pulse project, the hardware health monitor. Later, overheating house begat DIY Zoning, and since its inception, Pulse started to wither away into oblivion - a few years later I marked its status on SourceForge as "inactive", and today, there's not even a web page for it.

However, recent emergence of Android changed a lot. For a long time, lack of hardware support for DZ was a showstopper - nobody wants a zoning system that needs a computer in order to operate it. Smartphone, however, is a completely different deal.

Almost exactly a year ago I started planning for it. A month ago, I got my hands on the hardware. Today, I can say with confidence that G1 can deliver, and it does make sense to implement a control system with a mobile interface based on Android platform.

One of the lessons of DIY Zoning development was that it is a bad idea to have a monolithic system - I had to split it up three or four times before I was happy with the distributed features of the whole system. Not to repeat the same mistake, the application will be more generic than just a zoning system controller.

Hence, hereby the relaunch of the Pulse project is announced.

It'll be a short while before the feature set is established, the project site is again complete with content, and version control system will have the code - I just don't want to release half-baked barely functioning code prematurely, it is still in the works. It's just that privately expressed interest towards the project exceeded the critical mass recently, and I thought you folks would like to know what I'm working on.

Stay tuned.

Saturday, October 11, 2008

SourceForge Trackers Are Being Exploited

I don't remember valid bug submissions for a couple of years, all that it generates is blogspam, and the traffic is ever increasing. I think I'm gonna close it soon.

Saturday, August 30, 2008

And you thought your installation was bad...

Just saw this hilarious post.

Reminded me of being there and watching both the installation process, and the results - and I must tell you, those are not for the weak of heart.

The installation I saw was on the second floor, and they already had to use a crane. However, as the floor goes up, so does the price (and the danger). I don't think there are any cranes (at least that a regular person can afford) that can reach above, I'd say, fifth floor - and I've seen mini splits installed all the way up to 16th floor (that's the usual height of a residential high rise building).

The only way I can think of is to use professional climbers to haul the condenser up and fasten it to the wall, but then there's a question of connecting it and charging the system, which requires HVAC training and certification, and not always can be done from inside...

Things sure are interesting over there.

Friday, August 29, 2008

SketchUp + Energy Performance, part 4

(part 1)
(part 2)
(part 3)

I think I'm going to stop referring to HVAC-Calc, lest there be any confusion...

Anyway, the saga continues - and here's the last installment: See your building's energy performance - and note, it's free.




Let the fun begin.

Tuesday, August 19, 2008

Real Life Numbers

Had to shut off the workshop for a month. 850 sq ft that I didn't have to cool to 82°F with the average ambient temperature of 92°F resulted in $75 savings on the electric bill.

Of course, this number is not exact by any stretch of imagination, but it'll give you a good ballpark of what your actual HVAC expenses are, and give you some food for thought about the actual ROI on your HVAC related investments.

Monday, August 11, 2008

Who Needs A Thermostat, Take Three

There is a new application for Google Android platform, AutoHTN, which, among other things, purports to control the home HVAC.

Told ya...

Sunday, July 27, 2008

Extra Insulation For The Poor

Extreme circumstances call for extreme measures.

If you are not happy with your single pane windows, but don't have enough money to replace them with something better, and willing to live with the ugliness of a temporary solution (in these times of failing employment and skyrocketing prices of everything this may be quite acceptable), here's a way to deal with it:

Install a sheet of expanded polystyrene into the window.

They come in different sizes, the most convenient would be 2'x4' (or 4'x8' if you have a truck).

4x8 2" thick costs (at the moment of writing at my location) about $23. 2x4 costs less than $6.

2" thick sheet is R-7.8 (for comparison, a single pane window is R-1, triple pane window is R-3).

Thinner sheets cost less, but have significantly lower R value, so you be the judge of what you need.

These sheets are not completely opaque - they let just about the same amount of light as a heavy curtain, with the added benefit of preserving the spectrum (with a slight blue hue because of blue lettering on them).

A nice tool to cut these sheets with, should that be necessary, is a Japanese (pull style) double blade saw such as Vaughan Bear - it's a complete topic in itself, you'll love using this tool, much more exact and rewarding than a comparable size push saw.

Installing these makes a hell of a difference.

Thursday, July 10, 2008

The other side of the coin: mini-splits

Just returned from a trip to Eastern Europe.

Just as forced air HVAC systems are the king in the US, mini-splits and multi-splits rule over there. Of course, it is dictated by the environment - they are mostly being slapped on the walls of existing high rise buildings, where the choices are extremely limited - either mini-splits, or window shakers which are noisy and obstruct sunlight, or indoor portable units, which occupy a lot of already limited space.

I watched one of those being installed. Well, guess what, it is just as bad as it is here - the condenser turned out to be installed noticeably askew when we momentarily lost our vigilance, installers were visibly taken back by questions about how exactly they were charging the unit and eventually cut us off with "It's already been charged by the manufacturer", unfazed by questions about the relations between tubing length and operating pressures... Oh well, let's just hope that the HVAC manufacturer did their best and came up with some incredibly smart way to take that into account.

On the down side: God! They are sure an eyesore. Condenser is more or less OK since it is outside, but the air handler is HUGE.

On the up side: they seem to be orders of magnitude more efficient than big iron HVACs of US are. And, they're virtually silent, especially the condenser (it must be said, though, that I was witnessing the high end inverter system, cheaper models may not be as quiet).

Bottomline: if one of my HVACs decides to go south, I'll be replacing it with several mini-splits or multi-splits.

Even though they are said to be expensive, I'm sure that with my overinflated demand for quality I'll get just about the same price as I would get for a single forced air HVAC of similar capacity, plus advanced ability to place the unit where I want, not where the ducts go, plus advanced scheduling and shutoff capabilities, plus zoning out of the box, plus truckload of free space in the walls where the ducts used to be.

/me off investigating...