Controlling central heating (HVAC) through X-10

Post by **Mhwlng** » Tue Apr 15, 2008 3:11 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote"> I know it's supposed to work because it's all OpenTherm, but still I'm a bit surprised.
<hr height="1" noshade id="quote"></blockquote id="quote">I didn't test every function of the PC program, but it all looks ok...

I have an AGPO Econpact 4.
It originally came with a Honeywell thermostat, which looks exactly like the celcia 15.

(I didn't test the gateway with this honeywell thermostat...)

would you mind sharing the data format that you already found ?

Marcel

Post by **MindBender** » Tue Apr 15, 2008 3:54 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by mhwlng
would you mind sharing the data format that you already found ?<hr height="1" noshade id="quote"></blockquote id="quote">I will publish it, in due time. Giving preliminairy answers, maintaining them and typing long email threats takes too much time for now. I'd rather spend that time on getting my HomeSeer plugin to work.

Post by **Mhwlng** » Tue Apr 15, 2008 4:05 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by MindBender
maintaining them and typing long email threats takes too much time for now.
<hr height="1" noshade id="quote"></blockquote id="quote">ok, I won't bother you again with my questions..

I'm not sure why you've been promoting a remeha gateway based solution since 2006 and then you don't seem to be interested in sharing when others follow your advice ??

Never mind...
I'll figure it out and, as is the case with all my domotica stuff, I will open-source my work...

good luck with your plugin...

Marcel

Post by **MindBender** » Tue Apr 15, 2008 8:20 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by mhwlng
I'm not sure why you've been promoting a remeha gateway based solution since 2006 and then you don't seem to be interested in sharing when others follow your advice ??<hr height="1" noshade id="quote"></blockquote id="quote">
I'm sorry, but I'm detecting a bit of a strange attitude here. If I had oceans of time, I would have had this plugin in 2006 already. Since that time nobody showed any interest in contributing to this project, and that's totally cool with me. But please don't start blaming me for not spending time on sharing preliminary information in this early stage of the project, which may even cost more time if I need to rectify things later on.

If you have been waiting since 2006, I'm sure you can wait another couple of weeks. If not, you've been waiting a loooooooong time for something that took me about 5 minutes. [}:)]

Post by **Mhwlng** » Tue Apr 15, 2008 9:41 pm

whatever, dude...

attach working vb6 test application source code for everybody to use..

it reads room temperature, temperature setpoint and boiler temperature

and also writes temperature setpoint

Download Attachment:

remehatest2.zip 3.19KB

I needed more than 5 minutes to figure everything out,
So, you must be very good...

p.s. If anybody is interested :

I connected my gateway via a very old powerline ethernet adapter + EZL-200f rs232-ethernet converter (and virtual com port)...

Post by **MindBender** » Wed Apr 16, 2008 11:52 am

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by mhwlng
 whatever, dude...
attach working vb6 test application source code for everybody to use..
it reads room temperature, temperature setpoint and boiler temperature
and also writes temperature setpoint
<hr height="1" noshade id="quote"></blockquote id="quote">
Good work, well done! See? It's really not that hard and hardly worth waiting for somebody else to do it [;)].
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
I needed more than 5 minutes to figure everything out,
So, you must be very good...
<hr height="1" noshade id="quote"></blockquote id="quote">
Yes, I am [;)]. Nah, I bet anyone can immediately see how the protocol works. Figuring out the datagrams takes a little longer, because it's a little more work.

Some comments on your program:
You need to extend your it with ENQ-ACK/NACK. Before sending anything to the Gateway, your program needs to send and <ENQ> (0x05) character first. When it receives and <ACK> (0x1A) in reply, it can continue. If it receives a <NACK> (0x15) it should try again after some time. When a datagram is sent to the Gateway, it normally directly replies the answering datagram, but instead it could still reply a <NACK>. In that case you program has to go back to sending an <ENQ> again and it has to resend its datagram upon receiving an <ACK>.
Datagrams

Code: Select all

Datagrams look like this:
<STX><ADR><CHKa><STX><TYPE><DATA><CHKd><ETX>
Where:
<STX>  = Start of text character (0x02)
<ADR>  = Address, can be more than one byte, but I've only seen 1
         0x00 = Gateway
         0x0A = Computer
<CHKa> = Checksum of address bytes.
         This is calculated by adding all address bytes in one byte,
         allowing for roll-over. In practice, this is equal to the
         address byte, because there's only one of those.
<STX>  = Another start of text character (0x02)
<TYPE> = Type of datagram
<DATA> = The actual data, usually more 9 bytes, but may be abcent at
         all. The meaning of each byte differs per datagram type.
<CHKd> = Checksum of Type and Data bytes.
         This is calculated by adding the Type byte and all data
         bytes in one byte, allowing for roll-over.
<ETX>  = End of text character (0x03)

Request 'Temperatures':
 02 00 00 02 50 50 03
              |
              +------------------------------------ Request 'Temperatures'-datagram
Answer from Gateway:
 02 0A 0A 02 50 14 D7 14 99 26 00 00 00 02 00 10 03
              |  |  |  |  |  |  |  |  |  |  |
              |  |  |  |  |  |  |  |  |  |  +------
              |  |  |  |  |  |  |  |  |  +--------- Status Celcia
              |  |  |  |  |  |  |  |  +------------
              |  |  |  |  |  |  |  +---------------
              |  |  |  |  |  |  +------------------
              |  |  |  |  |  +--------------------- T Boiler Set, hexadecimal: 38
              |  |  |  |  +------------------------ T Room Set, 1/256th degrees hexadecimal: 60
              |  |  |  +--------------------------- T Room Set, whole degrees hexadecimal: 20
              |  |  +------------------------------ T Room, 1/256th degrees hexadecimal: 84
              |  +--------------------------------- T Room, degrees hexadecimal: 20
              +------------------------------------ 'Temperatures'-datagram

Request 'Boiler status':
 02 00 00 02 51 51 03
              |
              +------------------------------------ Request 'Boiler status'-datagram
Answer from Gateway:
 02 0A 0A 02 51 32 39 0A 00 0D 00 00 00 00 00 D3 03
              |  |  |  |  |  |  |  |  |  |  |
              |  |  |  |  |  |  |  |  |  |  +------
              |  |  |  |  |  |  |  |  |  +---------
              |  |  |  |  |  |  |  |  +------------
              |  |  |  |  |  |  |  +---------------
              |  |  |  |  |  |  +------------------
              |  |  |  |  |  +---------------------
              |  |  |  |  +------------------------
              |  |  |  +--------------------------- Status Boiler, hexadecimal: 10
              |  |  +------------------------------ Modulation level, hexadecimal: 57
              |  +--------------------------------- T Boiler, hexadecimal: 50
              +------------------------------------ 'Boiler status'-datagram

Request 'Counters':
 02 00 00 02 52 52 03
              |
              +------------------------------------ Request 'Boiler status'-datagram
Answer from Gateway:
 02 0A 0A 02 52 78 00 07 44 03 06 01 63 05 07 8E 03
              |  |  |  |  |  |  |  |  |  |  |
              |  |  |  |  |  |  |  |  |  +--+------ StartDHW divided by 10, decimal: 507
              |  |  |  |  |  |  |  +--+------------ HoursDHW, decimal: 163
              |  |  |  |  |  +--+------------------ StartsCH divided by 10, decimal: 306
              |  |  |  +--+------------------------ HoursCH, decimal: 744
              |  |  +------------------------------
              |  +---------------------------------
              +------------------------------------ 'Counters'-datagram

Request 'version info':
 02 00 00 02 53 53 03
              |
              +------------------------------------ Request 'Version Answer from Gateway:
 02 0A 0A 02 53 03 04 14 24 01 0B 02 00 00 00 A0 03
              |  |  |  |  |  |  |  |  |  |  |
              |  |  |  |  |  |  |  |  |  |  +------
              |  |  |  |  |  |  |  |  |  +---------
              |  |  |  |  |  |  |  |  +------------
              |  |  |  |  |  |  |  +--------------- Slave Member ID
              |  |  |  |  |  |  +------------------ Master Member ID
              |  |  |  |  |  +--------------------- Slave Product Type
              |  |  |  |  +------------------------ Slave Product Version
              |  |  |  +--------------------------- Master Product Type
              |  |  +------------------------------ GateWay Version
              | +---------------------------------- Master Product Version
              +------------------------------------ 'Version info'-datagram

I will continue to document this protocol here: http://nerdclub.nl/remeha_gateway/

Post by **Mhwlng** » Wed Apr 16, 2008 11:55 am

>>Some comments on your program:
>>You need to extend your it with ENQ-ACK/NACK
it actually does that... see init function...

amazing, by the way, how you suddenly found time in your busy schedule to publish this AFTER I already figured it out myself....

so, thanks for nothing...

Marcel

Post by **MindBender** » Wed Apr 16, 2008 11:58 am

I really don't like your attitude here, Marcel. I find the tone in your postings unprovoked offensive. I'd suggest you to moderate it a bit, or at least direct it at ideas, not at persons.

Post by **Bwired** » Wed Apr 16, 2008 2:18 pm

@Marcel
Is your Hvac system type AGPO Econpact 4 a copy of the Remeha Hvac? I'm not familiar with the brand. How do you connect the Remeha gateway to your Hvac, with RS232 DB9 pins?
Thanks Pieter

Post by **Snelvuur** » Wed Apr 16, 2008 2:19 pm

@marcel: we are all friends here, no need to be rude. your point is taken, but hey he did check your code and took the time to read through it and make a remark and show information about the datagrams.

Its better that you make a combined effort to make a good/nice solution here since i both think you guys can do more then i could ever do.

// Erik (binkey.nl)

Post by **Mhwlng** » Wed Apr 16, 2008 2:22 pm

I don't know if the AGPO Econpact 4 heater is a copy of the Remeha heater

I don't think so ?

opentherm is 2 wires so :

gateway has 4 screw terminals (opentherm in+out)
heater has 2 opentherm screw terminals
thermostat has 2 openterm screw terminals

heater -> gateway -> thermostat

gateway has also rs232 port used to read temp etc.

Post by **Bwired** » Wed Apr 16, 2008 2:55 pm

So you connect the gateway like this? If so then it could work on all opentherm HVAC systems
[img]="/uploaded/bwired/200694174613_opentherm.jpg"[/img]

Post by **Mhwlng** » Wed Apr 16, 2008 3:00 pm

yes and yes (so far, we only know for sure that it works with 2 heaters)

also note that this gateway is sold to be used with one specific thermostat (celcia 20)

no idea if it will work with others...

Marcel

Post by **MindBender** » Wed Apr 16, 2008 3:07 pm

@Pieter: Your drawing is more-or-less correct, but the 'interface device' doesn't interrupt the OpenTherm bus. It is just an additional node on the same bus. That's why I'm so surprised that it works on a different brand of boiler. But if it does, I think we can all agree on that being good News! However, I'm pretty sure there is a strong dependence on the Celcia 20 thermostat. My Gateway is mounted at a bit of an inconvenient location, so I cannot detach it simply for you to try things out.

From the other hands: Not all boiler manufacturers develop their own controller (or thermostat). They usually buy a OEM part at a specialized party and I don't think such a party invests much effort in developing a unique unique OpenTherm implementation for each customer. So different boilers may be compatible, be it not by design, but more by coincidence.

I've got a friend working as a developer at one of these parties: I'll ask him if he can tell us more.

Post by **Bwired** » Wed Apr 16, 2008 4:42 pm

@Marcel & Robert
That would be good News for sure!
I have a opentherm Nefit HRC24 with an advanced thermostat, also Nefit is known that they use a slightly different opentherm protocol

Where did you buy the Remeha Gateway, thinking about trying it out, even if I have to buy a Remeha Celcia 20