Automating our home heating.. Nest 3rd Gen in NZ?

Forums › Gadgets, robotics, home automation, electronics (including wearables) › Automating our home heating.. Nest 3rd Gen in NZ?

BuffyNZ

241 posts

Master Geek

#196074 18-May-2016 13:28

Hi folks,

I am getting some new heat pumps installed in our house, and am looking for how to get some automated temperature control up and running.

We have no existing thermostats.

Are something like Nest thermostats the way to go?

Does anyone have the 3rd gen ones up and running in NZ?

Any other suggestions or alternatives?

Recursion: See recursion.
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wellygary

8324 posts

Uber Geek

#1554795 18-May-2016 13:34

Generally Heat pumps come with built in thermostats, and it is hard to actually control them via anyother means,

I am not really aware of any heatpumps that will easily allow you to interface a 3rd party controller

BuffyNZ

241 posts

Master Geek

#1554998 18-May-2016 16:37

Thanks, the more I think about it the more I realize had not really thought through how it all would hang together.

I will look into if is worth getting a Daikin so I can integrate into openhab.

chimera

506 posts

Ultimate Geek

#1562807 31-May-2016 09:43

BuffyNZ:

Thanks, the more I think about it the more I realize had not really thought through how it all would hang together.

I will look into if is worth getting a Daikin so I can integrate into openhab.

Sorry to tag on your post - but I'm in a similar situation/wanting to do the same thing. I have HRV (Heat recovery ventilation) which does the "V" part quite well, but lacks the "H" part when most needed.

I recently built an ESP8266 to send HRV data to OpenHAB via MQTT (http://www.geekzone.co.nz/forums.asp?forumid=141&topicid=195424) - this works quite well.

It starts to get interesting when you plot house vs roof vs outside temperatures (outside temperature data in my case, provided by Wunderground, roof and house from the HRV unit) The data below is only over the past 24 hours...

Roof seems to average about 3 degrees warmer than outdoor air. However goal is to maintain indoor around 20 degrees. My house is fully insulated, however its not double glazed (which makes the BIGGEST difference to a homes retention of heat!)

So I'm considering how effective it would be to utilise a 3rd party heating system to inject warm air directly into HRV intake based on rules in OpenHAB from data obtained from the graph above (even if it were a 'dumb' on/off unit, I could run another Arduino or ESP8266 in the ceiling controlling it via relays or similar) and perhaps the reverse in summer (although would rather put in an extractor venting ceiling heat outside and drawing cooler air in from under the house) It would also be nicer to have control over the temperature/thermostat up/down rather than an off/on approach, but open to ideas.

And I know that while a heat pump is perhaps the most efficient in terms of heating, it only directs that air into the room (and perhaps nearby rooms) its located in (I have quite a large L shape house) A heat transfer kit would be needed to utilised to move that warm air to other areas of the house but whilst I have an HRV, I figured I may as well make use of it. I believe HRV sell heating unit plug-ins to the HRV system, but knowing their pricing I'm not willing to fork out thousands more. I'd rather use my own data and build something customised. I could also wrap the HRV ducting with insulation to make it more efficient as I have reasonably good access into the ceiling cavity.

HRV intakes are just large round openings in the side of the fan. I could control the heating output to cover the HRV inlet when its on, and open back out when its off (by servo's connected to Arduino) Or perhaps more simply pressure from the air output from the heating device could cover the HRV inlet when on, and spring back when off.

Any ideas on products that could be utilised to supplement this?

Disrespective

1926 posts

Uber Geek

#1562883 31-May-2016 10:59

The Daikin OpenHAB binding is pretty good. It uses a java api to do it, but basically you can send HTTP commands to connected Daikin units for control and reporting of parameters. See here for examples: http://forums.whirlpool.net.au/forum-replies.cfm?t=2440219&#r6

reven

3743 posts

Uber Geek

Trusted

#1562893 31-May-2016 11:14

home automation would work, thats what I use.

I have a panasonic heat pump with an intesishome wifi module.

I have heaps of temp sensors around the house connected to my zwave network. I take the average of these temperatures to determine the "house temperature" (only bedroom temps at night when living areas are unoccupied). if those temps get above a certain temp then opnehab turns the heat pump on cool mode, or if it drops below a certain temp it turns it on heat. then it turns everything off when people leave the house, or 30 mins after when all the tvs and lights go off at night.

BuffyNZ

241 posts

Master Geek

#1562918 31-May-2016 11:36

reven:

then it turns everything off when people leave the house, or 30 mins after when all the tvs and lights go off at night.

I am curious about what rule(s) you use to tell when everyone is out of the house..

I thought that if I use just PIR's, someone sitting still to watch TV would be missed.

I could use mobile phone locations, but the kids never take theirs out of the house.

The only thing I can think of is 'When the alarm is armed'.

timmmay

20580 posts

Uber Geek

Trusted

Lifetime subscriber

#1562919 31-May-2016 11:39

I have a couple of US$35 ali express units that turn the heat pumps on and off according to a preset timer. Works fine, very easy, app is a bit rubbish but works, it might not get nerd points or do full integration but it does what I need - makes the house the temperature I want, when I want it. Have a look at this thread. Product is here.

Tradepub

Free professional, reference and technical white papers (affiliate link).

reven

3743 posts

Uber Geek

Trusted

#1562920 31-May-2016 11:40

BuffyNZ:

reven:

then it turns everything off when people leave the house, or 30 mins after when all the tvs and lights go off at night.

I am curious about what rule(s) you use to tell when everyone is out of the house..

I thought that if I use just PIR's, someone sitting still to watch TV would be missed.

I could use mobile phone locations, but the kids never take theirs out of the house.

The only thing I can think of is 'When the alarm is armed'.

i use ip addresses of phones/watches/gps mostly. i also use this to auto arm the house alarm. i do a few other things, but not to determine the house global presence but room specific presence like when the computer is unlocked turn on set computer in use to true, when shutdown/locked (auto lock on idle) set to off. when tv ip is connected, tv in use to true. when harmony hub action started, room presence on etc.

but for the heat pump its basically tied to the same ip/gps conditions i use for my alarm.

SumnerBoy

2074 posts

Uber Geek

ID Verified

Lifetime subscriber

#1562954 31-May-2016 12:28

Check out this blog post (http://dreamgreenhouse.com/projects/2013/presence/index.php) for a good way to track presence without requiring constant sensor events. Basically you need a sensor on every external door and then as many internal sensors as you can manage. If any of the external doors are opened we assume the *wasp has escaped*. As soon as all external doors are closed and you detect any presence inside the house we assume the *wasp is inside* and cannot escape until one of the external doors is opened.

Better explanation and detail in the blog but I have implemented this and it is extremely good for presence detection. I have it setup for the whole house and a few key rooms (living room and garage). YMMV.

Disrespective

1926 posts

Uber Geek

#1563010 31-May-2016 14:19

I'm planning on doing presence detection through mac addresses and a DDWRT script which checks the arp table of my router. It just looks at what devices are connected and if one of them is mine or my wife's phone then it uses openhab items. See here: https://community.openhab.org/t/dd-wrt-presence-detection-with-arp-for-openhab/9521

It can also allow for monitoring of other devices (TV etc) which are turned on and connected to the network for other rules and scheduling.

Edit: This obviously provides a more overall picture of presence. Not the fine grained room-by-room approach.

chimera

506 posts

Ultimate Geek

#1563073 31-May-2016 15:20

Disrespective:

I'm planning on doing presence detection through mac addresses and a DDWRT script which checks the arp table of my router. It just looks at what devices are connected and if one of them is mine or my wife's phone then it uses openhab items. See here: https://community.openhab.org/t/dd-wrt-presence-detection-with-arp-for-openhab/9521

It can also allow for monitoring of other devices (TV etc) which are turned on and connected to the network for other rules and scheduling.

Edit: This obviously provides a more overall picture of presence. Not the fine grained room-by-room approach.

Only briefly looked at this, and it looks like a great idea - but is there any reason you can't just run this on the same box as OpenHAB is running on and send curl commands to itself?

I run OpenHAB on CHIP. Its Debian Linux based as well, easy enough to script and cron. The only thing I could think of is it taxing the CPU if polling every second.

Disrespective

1926 posts

Uber Geek

#1563088 31-May-2016 15:46

I'm not clued up enough to comment about what would be best to run it on to be honest. Would curl commands be able to determine if my device is connected to the wifi 5g radio?

chimera

506 posts

Ultimate Geek

#1563090 31-May-2016 15:58

Disrespective:

I'm not clued up enough to comment about what would be best to run it on to be honest. Would curl commands be able to determine if my device is connected to the wifi 5g radio?

Not curl commands, all curl does is send HTTP, HTTPS, FTP (and similar protocols) data via command line.

Other commands can be used to determine MAC addresses, a simple 'arp' command at Linux will show the MAC address table. I guess issue is that MAC addresses by default stay in cache for 15 minutes... which I may have just answered my own question...

There will most definitely be alternate ways under Linux. I don't see why powering up yet another device (Linksys running DDWRT for example) is needed. I have a Linksys here right now running DDWRT (my old AP) which I could use but I'd prefer it all on a single device to remove other single points of failure.

I'll play around with some scripting and see what I can come up with...

Aredwood

3885 posts

Uber Geek

#1563912 1-Jun-2016 23:22

Don't bother trying to re-purpose the HRV system into a ducted heating system. As it will be taking in cold roof space air, heating it, putting that air into the house. Which will then be pushing warm air from inside of the house to outside. Proper way to do ducted heating is to have a return air intake in a central part of the house (usually the hallway). that air is then heated and the put back into the house. Cheaper to run as the return air is often only slightly colder than the desired temp.

You would then be able to write some rules to use the HRV if heat is available in roof space. Otherwise use the central heater. And an HRV only rule for when no one is at home.

chimera

506 posts

Ultimate Geek

#1563962 2-Jun-2016 08:21

Aredwood:

Don't bother trying to re-purpose the HRV system into a ducted heating system. As it will be taking in cold roof space air, heating it, putting that air into the house. Which will then be pushing warm air from inside of the house to outside. Proper way to do ducted heating is to have a return air intake in a central part of the house (usually the hallway). that air is then heated and the put back into the house. Cheaper to run as the return air is often only slightly colder than the desired temp.

You would then be able to write some rules to use the HRV if heat is available in roof space. Otherwise use the central heater. And an HRV only rule for when no one is at home.

I'm aware of that, hence why I mentioned putting a heating appliance directly in front of the HRV inlet. It makes no sense to heat the entire roof cavity just to get some of that warm air around the house. I created my own heat transfer system, as the lounge roof is high (have in-wall gas heater) which then directs heat to the hallway if the thermostat goes above X degrees. It was more a test than anything, and is highly inefficient. I would be better off directing that pipe directly into the front of the HRV inlet rather than hallway 10m away. But then I'd have to calculate heat loss through the ducting. Eh...