OTGW and Intergas - no return temp reported

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OTGW and Intergas - no return temp reported

Postby paulockenden » Thu Nov 29, 2018 11:43 am

I'm using @Cyril's excellent little Orange Pi Zero OTGW board, and an Intergas Eco RF combi boiler (I believe it's sold with a slightly different model name in other markets).

All is working very well EXCEPT for the fact that the boiler isn't reporting heating return temperature via Opentherm (it's visible via Intergas's own InComfort system, so the boiler does know the details - it just isn't exposing it to OpenTherm).

I read somewhere about setting an 'alternative' using AA=28, but that doesn't seem to help (unless I'm doing something wrong).

Just posting here in case anyone else is in a similar situation and has managed to figure out a solution.

Thanks a million,

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Re: OTGW and Intergas - no return temp reported

Postby Cooter » Fri Nov 30, 2018 2:14 pm

I have the same problem with an Intergas HRE. But it does send the DHW temperature. I think that is the same in CH mode.
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Re: OTGW and Intergas - no return temp reported

Postby hvxl » Mon Dec 03, 2018 5:24 pm

If information isn't exposed to Opentherm, then obviously the OTGW cannot report it.

Whether you're doing something wrong is impossible to tell without more data. The easiest way determine it is to look at the Statistics tab in otmonitor. If ID 28 Return Water Temperature is present there, but its Direction is Unk, then your boiler doesn't report it (or you have issued a UI=28 command). If ID 28 does not show up there, even after otmonitor has been running for while, check if there are any other IDs with direction Unk. If there are, you did something wrong. If there are none, then your thermostat may only send a very limited set of IDs that are all supported by the boiler and the OTGW doesn't have a chance to send the ID 28. Or maybe your boiler does not correctly indicate that it doesn't support some IDs. In that case you can manually set some uninteresting IDs to Unk via the UI command.

If you provide a few minutes of log from otmonitor, I can also take a look for you.
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Re: OTGW and Intergas - no return temp reported

Postby mrten » Fri Dec 21, 2018 10:08 am

AA=28 can help, but there must be an ID that is unknown before the 'alternative' message can be inserted. Monitor the messages for a while and look for one that is obviously unneeded, with my Remeha Calenta/Remeha iSense setup there are no unknown messages over the OpenTherm so I had to cancel the 'solar storage temperature' first with UI=29 before the AA=28 started working.
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