Aprilaire THE thermostat choice?

[Rupp]

I am trying to choose the right thermostat and I'm new to all of this home automation stuff. I will have several heating zones in a mountain cabin. I need to keep the heat up to around 40F to prevent pipes from freezing when I'm gone, and I'd like to be able to turn on the heat before I drive up.

My research so far indicates that the Aprilaire is the device of choice. Since I do embedded computer stuff for a living, I appreciate the RS422 communication.

I have heard that the protocol the thermostat uses is available but I have not found it anywhere. Can someone point me to that? I probably won't actually build my own controller/web interface since it would take me longer than my time is worth to develop one off code, but it would be nice to know its there.

Thank you.

The HAI line of thermostats are the easiest to install and interface to. They are also one of the most affordable line of thermostats (except for the Z-Wave model). They use simple RS232 and the protocol is freely available. http://www.hometech.com/modules/therm.html#HAI

 

[rfdesq]

Just an FYI, RCS is coming out with a new Ethernet thermostat. Kirk from ELK is aware of it as their booths were right across from each other at EHX.

 

[beelzerob]

The HAI line of thermostats are the easiest to install and interface to. They are also one of the most affordable line of thermostats (except for the Z-Wave model). They use simple RS232 and the protocol is freely available. http://www.hometech.com/modules/therm.html#HAI

Are they along the same lines as the Aprilaire...just run a Cat5 wire to it and I'll be good to go?

 

[gcimmino]

My research so far indicates that the Aprilaire is the device of choice. Since I do embedded computer stuff for a living, I appreciate the RS422 communication.

I have heard that the protocol the thermostat uses is available but I have not found it anywhere. Can someone point me to that? I probably won't actually build my own controller/web interface since it would take me longer than my time is worth to develop one off code, but it would be nice to know its there.

Try this for the protocol:

http://www.aprilairecontractor.com/pdfs/88...rs%20Manual.pdf

If that doesn't work directly, go to http://www.aprilairecontractor.com/, Click on Home Automation, Register, and Click the 8870 link in the middle of the page in the New section. You'll find all the docs for the family of components.

 

[phabib]

thanks for the responses. Ethernet thermostats sound interesting. Maybe they'll be out by the time I really need to get something installed.

A couple more questions, since the Aprilaire doesn't say its a setback thermostat, does that mean that the setback program needs to run on some other device that would send commands to the thermostats? If so, does the 8825 controller do that job, or does it only connect the thermostats to the outside world?

Thanks.

 

[shenandoah75]

"Are they along the same lines as the Aprilaire...just run a Cat5 wire to it and I'll be good to go?"


Yep on the HAI, it really is that simple. I have two of them installed... My only gripe and not sure if politics123 has the same, but i've got a problem with being able to keep the front cover tightly closed. I know it's cause the cat5 wire comign through the back/wall is pretty thck. And it just seems to push enough that one corner is generally slightly lose. I may try again tonight to see if i can resolve. But i think i have to admit the overall look/feel/build quality of the Aprilair seems a bit higher.


The seperate design of the RCS units ruled that out given the ease of the other two

The Aprilaire is nice, but ~2x the price of HAI, i think its price versus your perception of value which is different for everyone. My father in law is an AC contractor and he thought i was nuts buying the HAI given what he could have given me a standard white/rogers programmable for.


Just curious, can you get the remote temp/humidty readings passed back to the elk somehow?

 

[Rupp]

Guys,
With Aprilaire don't you need the thermostat, the distribution panel and the protocol adapter to convert the RS485 to RS232? That's over $400. Am I reading this correctly?

 

[shenandoah75]

Ya i'm dumb... i thought the 8870 was standalone and only RCS had the panel/etc...

in that case, now i remmber why i chose HAI

 

[politics123]

Yep on the HAI, it really is that simple. I have two of them installed... My only gripe and not sure if politics123 has the same, but i've got a problem with being able to keep the front cover tightly closed. I know it's cause the cat5 wire comign through the back/wall is pretty thck. And it just seems to push enough that one corner is generally slightly lose. I may try again tonight to see if i can resolve. But i think i have to admit the overall look/feel/build quality of the Aprilair seems a bit higher.

Yeah, I have a similar problem. You can remove more of of the insultation and it should help. I actually tape my wires to the back plate (be careful not to cover the vent hole) so that they aren't in the way of the circuitry when you put the cover on. It's a mild pain in the ass, but once done, you never have to remove it again.

Funny, your comment reminded me of me... I posted a question about 6 months ago entitled "ELK Thermostats -- could it really be this easy?"

http://www.cocoontech.com/index.php?showto...7009&hl=HAI

Anyway, it was surprisingly easy, and I love having my tstats automated.

Let me give you an installation hint. For retrofits, use your digicam and take a picture of the terminal strip (with the colored wires) so in case you want to revert, its easy to remember what was connected to what.

 

[magrann]

Rupp.

I don't think you need the distribution panel for the Aprilaire. I just finished hooking one up to Elk using just the 8870 tstat and the adaptor. I guess the distribution panel is for hooking a multiple tsats, supposedly it makes things easier.

Mike

 

[IVB]

Rupp.

I don't think you need the distribution panel for the Aprilaire. I just finished hooking one up to Elk using just the 8870 tstat and the adaptor. I guess the distribution panel is for hooking a multiple tsats, supposedly it makes things easier.

Mike

That is correct; i only had the 8870 & 8811 adapter for a long time. I got a 2nd 8870, and opted for the distro panel rather than daisy-chain.

Then again, I still haven't gotten it to work, but i'm fairly certain I screwed up the wiring and I'm too damn lazy to fix it.

 

[DJK]

Sorry to hijack this thread but another Aprilaire question:

My contractor is wiring the t-stats back to a central location separate from my closet. Does it matter if I run wire from this location to my closet, or should it run from t-stat to closet?

 

[magrann]

DJK

I think that is up to you and I guess it might depend on how you plan to control it. For me, I ran cat5 from the tstat back to my closet. There I connected the wire to the aprilaire adaptor and then to the Elk M1XSP. However, I think I could of run the cat 5 to wherever and then hook into the M1XSP at that location and run the M1xsp back the closet. Either way you want something running back to your closet, wether that be from the tstat or from the hvac unit. Don't know if this helps.

Mike

 

[DJK]

Mike,

Yes, will definitely wire to the closet!

I guess I'll run from the T-stats to the ELK in case I ever switch them out, then I don't have to worry about which wires went to what at the HVAC side. This makes sense to me, but also my first time doing this.

Does this make sense to everybody (anybody) else?

Thanks!