Remote control of Remeha heater

Post by **emomartin** » Wed Sep 24, 2008 8:57 pm

Hi,
Remeha gas heating devices (like Avanta and others) offer a connector for a serial (RS 232) cable to be connected to a PC, and a software which allows the remote control and data logging of the parameters and so on (Recom Interface and Software). This sounds great!

Does anybody operate this and has some experience with it?

I would be interested what parameters could be set via the software, e.g. is it possible to modulate the power of the heater? I have some further questions to the interface.

Thanks!

Post by **jwbuiten** » Thu Sep 25, 2008 9:35 am

There are a few members with experience with the remeha interface including myself.
To interface with the remeha system a remeha gateway is needed which can be connected to the pc over RS232.

The following topic contains a lot of information about the remeha integration: Controlling central heating (HVAC) through X-10

(If you had entered the search term 'remeha' in the search box you had found all this information by yourself....)

Edit:
I see that you are already involved in that topic. That's ok.

About your question about interfacing with the remeha device. You really need the gateway because this is the only way to communicate with the remeha device!

Post by **MindBender** » Thu Sep 25, 2008 10:50 am

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by jwbuiten
 About your question about interfacing with the remeha device. You really need the gateway because this is the only way to communicate with the remeha device!<hr height="1" noshade id="quote"></blockquote id="quote">That's not entirely true; My Remeha Quinta heater has a boxed header connector at it's front panel. This is most likely used by service engineers to modify the boilers internal settings. I'm quite sure there's a big overlap between these settings and the ones available through the GateWay. Perhaps a couple of things are only accessible through this port, but I fail to see why one would want to tinker with these settings; I'm quite familiar with control algorithms and the specific problems involved when trying to control houses temperature, but I would feel very uncomfortable changing any of the heater's internal parameters because there's a big chance on messing things up.

Can you please share your intentions with us?

Secondly, the protocol itself is quite easy to reverse-engineer if you have two nodes already speaking it. The only thing you need to get that conversation going is a fitting cable. If your planning on tinkering with the heater's internal settings, I assume you have no problem in opening up it's internal controller an see where the pins of the connector are ending up. If you draw a small diagram and post it here, I can try to help you out. But I don't have any ambitions in that direction myself because it will void my 10 year warranty and it serves little purpose to me.

Post by **jwbuiten** » Thu Sep 25, 2008 2:33 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by MindBender
That's not entirely true; My Remeha Quinta heater has a boxed header connector at it's front panel. ... but I would feel very uncomfortable changing any of the heater's internal parameters because there's a big chance on messing things up.<hr height="1" noshade id="quote"></blockquote id="quote">

Yes I know... At the time I wrote this I realized that there was a second option. Besides this I totaly agree with you that is is not comfortable at all to change the direct heater settings via the engineering interface!

Post by **emomartin** » Thu Sep 25, 2008 2:40 pm

Hi,
thanks for the replies.

To explain my intention: I have a quite complicated heating system with thermical solar panels, water-bearing wood oven and the Remeha heating device, all operating on a large buffer storage for the hot water. The whole system is controlled by a quite advanced universal control device (UVR 1611, http://www.ta.co.at/content/blogcategory/14/32/lang,en/), which directly controls the pumps, the switches and whatever is needed, and allows a continuous data logging and PC connection for observe and optimizing the system behaviour.
Usually this control can also modulate the power output of the heating device, so that the output can be adjusted to the actual needs. This however requires a special analogue interface of the heating (0-10 Volt), which unfortunately is not available at the Avanta.

So I am seeking for another possibility to control the power out put of the heating device. It should not be too complicated, and it should not involve other control components like OpenTherm room thermostat, as the final control has to be at the existing UVR 1611 control.

Actually I have already found that it seems impossible to do this directly via the OpenTherm protocol. And I think it would be costly and quite complicated to introduce an extra device like the remeha gateway, as I would need even further devices to control this one, and I am even not sure if the modulation of the power output would be possible with the gateway (this is an advanced feature).

On the other hand remeha offers a cable called Recom Interface
http://nl.remeha.com/index.php?eID=tx_c ... bdf691c85b
which realized a direct RS 232 connection to the heating device, and a software
http://www.remeha.info/business/index.php?type=1&id=124
which allows you to control the device completely and to log the data and error messages etc.. This seems to be a solution for my problem (and should be very interesting for other purposes also).

However, as far as I know, the cable costs more than 200 EURO (!), which I find is too much for a cable. So I would like to ask someone for informations about this cable, I think I might be able to easily build it on my own.

By the way: the cable is connected to the heating device by a connector called "X10". see
http://documentatie.remeha.info/documen ... 2-0106.pdf , page 20 (I have the Avanta plus solo, this is the name of a slightly modified version sold in Germany). However, the other connectors are called X1, X2, ..., so it is coincidently. Or could it be that there is some connection to the X-10 protocol you are mentioning (which I do not know).

So, maybe this RECOM interface might be interesting for you also (at least if it does not cost 2000 EURO)? Is there anybody who has this RECOM interface?

Post by **emomartin** » Thu Sep 25, 2008 2:42 pm

Sorry, I mean:

So, maybe this RECOM interface might be interesting for you also (at least if it does not cost 200 EURO)? Is there anybody who has this RECOM interface?

Post by **Pieterpaul** » Thu Sep 25, 2008 5:42 pm

I don't think the interface uses the X10 protocol that is discussed in other topics on this forum, as that form of X10 is a power line protocol.
I have no knowledge of the RECOM interface or the Remeha, so I can't help you there.
Are you sure the 200euro is for the cable and not for the SW?

/PP

Post by **emomartin** » Thu Sep 25, 2008 5:58 pm

Yes, the 200 EUR is for the cable, the software can be downloaded freely from the website.

Post by **Pieterpaul** » Thu Sep 25, 2008 7:36 pm

Interesting concept. Must be quite a cable [:)]

Post by **MindBender** » Fri Sep 26, 2008 9:26 am

The cable is probably a license for the software, instead of an dongle sytem. The cable itself is probably not much more than an RS-232 level shifter (eg. MAX232, MAX3232) to convert TTL signalling levels into RS-232 signalling levels and back. No offense, but if this doesn't sound familiar to you, you're not very likely to succeed because this is the simplest part.

You first roughly need to find out the functions of the pins in the boxed header connector. Power and ground are probably the easiest to find. Make sure the power you find is really power and not just a logic signal. You need to open the unit to trace it back. Next you need to find TxD and RxD signals. TxD is usually logic high, RxD is usually low. They will likely lead to an internal microcontroller.

In this stage you need a good digital multi meter. Post the voltages measured on each pin and their assumed function. Type numbers of the ICs the signals lead to and the pin numbers involved are helpful too.

Post by **emomartin** » Fri Sep 26, 2008 8:34 pm

Thank you very much for the hints. I will try it at the weekend.
I do not think that the cable has the function of a dongle, because I can run the software with no message sounding like this. I just have a status "no heater found" and "communication error"

Post by **emomartin** » Sun Oct 12, 2008 11:56 pm

Sorry that I was not replying to your hints in the meanwhile. I found another solution reasonably to solve the problem (control of the Remeha heating device with realisation of power reduction), so the RS232 interface is not anymore required for me.
Maybe I will try again in a while, for "academic interest".

Thanks for your interest.

Post by **gdfde** » Tue Jan 24, 2012 10:16 pm

emomartin, what was your "other" way to connect to the heater?

Post by **barrydegraaff** » Fri Mar 23, 2012 1:10 pm

I have documented a simplified version of the remeha recom interface cable, check here:
http://www.barrydegraaff.tk/blog/index. ... 0323093423

No level shifter max232 or bcp needed, just a USB-to-ttl serial converter, 6 dollars on ebay and a telephone headset cord, or an RJ-9 connector

Post by **Digit** » Fri Mar 23, 2012 4:02 pm

Hi Barry,
Thanks for mentioning me on your blog

But I'm sorry, what you're saying is not 100% correct.
I don't use a USB to Serial adapter; the RS232 output goes to a RFXCOM Serial port as you can read here:
http://blog.hekkers.net/2010/10/16/conn ... a-calenta/
Your solution is also mentioned btw, I wrote about it for those who don't want to take the RS232 road:
http://blog.hekkers.net/2011/03/14/reme ... revisited/

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