Market Research

[davegravy]

If anyone's interested in tailoring their dev efforts to match what consumers want, here's a potentially useful poll, albeit a disappointing sample size (N=38):

http://robohub.org/smart-homes-my-home-my-comfort-say-readers/

[Marie.O]

I am always laughing when I see people wanting to control the temperature in a room. This must be something from a different country, or mind set.

In my mindset, I set the temperature for a room once, I might modify it empirical over time, but never ever do I change the temperature in a room daily or on a time schedule. Way more expensive to reheat a room, than to keep a room at a specific temperature. Maybe other countries/homes are different, but that is the scientific consensus in Germany.

[davegravy]

I agree Posde, but one thing that's high on my (SWMBO's) wishlist in my home is the ability to have multiple thermal sensors around the house and automate-able, retrofit-able dampers such that there is a more even distribution of thermal energy.

I've played around with manual dampers to no end, and it's a very difficult (moving) target.

[Esperanto]

In my mindset, I set the temperature for a room once, I might modify it empirical over time, but never ever do I change the temperature in a room daily or on a time schedule. Way more expensive to reheat a room, than to keep a room at a specific temperature. Maybe other countries/homes are different, but that is the scientific consensus in Germany.

If that is the case we still have along way to go. I never heard about that yet. Here in the Netherlands the temperature is not set to a constant but also not totally to 0 at night. I always thought that it was cheaper to lower the temp a bit but not to much. But as u say the experts know best. Plain logic I think that the bigger the temp difference the bigger the loss and it also depends on the amount of isolation your room has.

[totallymaxed]

I agree Posde, but one thing that's high on my (SWMBO's) wishlist in my home is the ability to have multiple thermal sensors around the house and automate-able, retrofit-able dampers such that there is a more even distribution of thermal energy.

I've played around with manual dampers to no end, and it's a very difficult (moving) target.

We see a lot of demand from our installers for improved control of zones around a home. So I agree 100% with you that zoned balancing of thermal energy is one of the next big growth areas. Aligned with this is the ability to learn the patterns of usage of spaces in a home over time (this is really largely where Nest is coming from) so that optimal energy input based on use patterns is achieved.

[_if_]

I am always laughing when I see people wanting to control the temperature in a room. This must be something from a different country, or mind set.

In my mindset, I set the temperature for a room once, I might modify it empirical over time, but never ever do I change the temperature in a room daily or on a time schedule. Way more expensive to reheat a room, than to keep a room at a specific temperature. Maybe other countries/homes are different, but that is the scientific consensus in Germany.

the point may be, in the case of a central heatingsystem, you set the temperature for each room but there is no sensor which checks how warm it really is in each room (they often just have an outside sensor). now when you have big windows in a room and sun is shining the room would be warm enough without heating. when heating is on as well, it would get too warm...

my 2 cents
IF

[totallymaxed]

the point may be, in the case of a central heatingsystem, you set the temperature for each room but there is no sensor which checks how warm it really is in each room (they often just have an outside sensor). now when you have big windows in a room and sun is shining the room would be warm enough without heating. when heating is on as well, it would get too warm...

my 2 cents
IF

You make a very good point. I agree that individual temp sensors in each zone/room are essential. Of course one of the limitations of the Nest is exactly that - it only has a single temperature sensor and can only therefore measure the ambient temperature in the location that you installed it in.

Andy

[davegravy]

Also great would be the ability to detect temperature differences between inside and outside, and use a larger/smaller portion of filtered outdoor air to cool or heat the house.

I review a lot of HVAC designs for proposed commercial buildings and they all seem to be doing stuff like this nowdays.

[totallymaxed]

Also great would be the ability to detect temperature differences between inside and outside, and use a larger/smaller portion of filtered outdoor air to cool or heat the house.

I review a lot of HVAC designs for proposed commercial buildings and they all seem to be doing stuff like this nowdays.

Agreed re the relative outside/inside temperature comparison. Commercial installations always lead the way on theses types of innovation. Obviously presence detection in each room/zone is also helpful too to provide the 'is a human in the room' and allow the system to potentially build up an occupancy graph.

We're playing around with something that we are currently calling 'RaspSensor' for the Raspberry Pi. Its a software package that can be installed on Raspian that provides a simple SOAP API to any 2 wire sensors that are attached to a Rpi. The idea is that you'd just place Wifi equpped Rpi's anywhere you need some sensors. The Rpi is so affordable and compact that placing even 8-10 of them around your house is low cost compared to anything else we've found and would enable a rich sensor package to be located in any room/zone ie temp/humidity/ambient Light/ etc etc.

Andy

[Marie.O]

@_IF_

the central heating sets the designated maximum temperature. Each room has its own thermostate which is set once and forgot about. At least that's what I do.

@esperegu

There is german page somewhere that describes the total energy needed to reheat an area after it had been shutdown for the night. The consense is, it doesn't make any sense to do it.

@totallymaxed

re specific zones of comfort, see what I wrote to _IF_. Changing the zones is something that is only viable if you have devices that change the temperature fast. If you use regular floor heating, the time it takes to reheat the room is way too long. If you have other types of heat/cool inducing techniques this might be a different case.

[totallymaxed]

@_IF_

the central heating sets the designated maximum temperature. Each room has its own thermostate which is set once and forgot about. At least that's what I do.

@esperegu

There is german page somewhere that describes the total energy needed to reheat an area after it had been shutdown for the night. The consense is, it doesn't make any sense to do it.

@totallymaxed

re specific zones of comfort, see what I wrote to _IF_. Changing the zones is something that is only viable if you have devices that change the temperature fast. If you use regular floor heating, the time it takes to reheat the room is way too long. If you have other types of heat/cool inducing techniques this might be a different case.

If you have a pure underfloor system with its inherent high latency and thermal inertia then I'd agree. But many properties do not have that kind of system. Full heat recovering systems with heat/cooling in one system for example can take a room up or down in temp very quickly indeed (while recovering most of the sunk energy too). These are quite common here and in the US now in bigger houses, and increasingly in modern apartment developments.

So I do agree in pure underfloor heated properties constant running at fixed settings is probably the best option.

Andy

[SBCC]

I am working on a HVAC zone controller now. I shelved it about a year ago but have been meaning to pick it back up again. I have one working based on X-10 thermostats but wanted a single device to sample temperature as well as control the dampers. The motorized dampers I am using have been running for years without an issue. There will also be a moisture sensor as well. The device will be quite cheap to make. My biggest issue is controlling the device from each zone location. I got sidetracked by that. I wanted a simple and cheap touch pad that would fit into a j-box.