Monitor boiler parameters when using an OT Bridge, a HGI80 and Evohome

[bruce_miranda]

Yes correct, all of the boiler parameters that are updated every 5mins via the OT interface are no longer being asked for by the Controller and hence not visible on Domoticz.
I might look to modify Domoticz at some point to get the HGI80 to request for this information instead of simply reading the messages that were already being requested.

[oxygen]

I guess your suggested approach (get Domoticz to get the HGI80 to collect OT data) might solve multiple "issues" on the current way requests/data is handled:
- Currently, I think I'm missing the thermostat only data.
- I'm also missing data available on the boiler only (such as the external temperature)

Funny thing is that my understanding now is that the error codes you managed to implement were actually known by the evohome controller, but never displayed on the controller interface.
I'll see to request the firmware upgrade then.

[philchillbill]

Since the beta firmware, the controller no longer seems to be requesting the boiler parameters off the OT Bridge. So all the Domoticz OT Boiler devices don't get updated. Boiler modulation was still being received on another message, so that is still being updated. I will look to see how I can bring these back into Domoticz, if Resideo won't.

Funny thing is, Boiler Modulation has not been updated for me since Oct 1st while e.g. Fault Logging was updated on December 1st with a Low Batt warning. I'm on 19.33. I have a long delay set in Domoticz before s sensor turns red which is why I had not spotted it earlier. Based on you comment, BM should be updating but it's not.

[zxdavb]

I don't have an OTB, so can't comment with 100% confidence, but I have the benefit of a few people's logs.

I seems to me that all the OTB systems I've seen, the controller periodically (every 300 secs) asks (i.e. issues an RQ) for:
- 05: Fault flags & OEM fault code
- 11: Relative modulation level
- 12: Central heating water pressure
- 13: DHW flow rate (litres/minute)
- 19: Boiler water temperature
- 1A: DHW temperature

In addition, some other controllers regularly (but not periodically, it seems) ask for:
- 1C: Return water temperature
- 73: OEM diagnostic code

I don't know why there is this difference, it could simply be a state thing.

This is an example of such a log (note the msg_id is the 3rd byte in the payload):

2020-10-21T09:54:41.077915 070 RQ --- 01:123456 63:262143 --:------ 3220 005 0000050000
2020-10-21T09:54:41.723184 049 RP --- 63:262143 01:123456 --:------ 3220 005 00F0050000
2020-10-21T09:54:41.877954 072 RQ --- 01:123456 63:262143 --:------ 3220 005 0000110000
2020-10-21T09:54:42.262205 049 RP --- 63:262143 01:123456 --:------ 3220 005 00C0110000
2020-10-21T09:54:42.278075 072 RQ --- 01:123456 63:262143 --:------ 3220 005 0000120000
2020-10-21T09:54:42.801189 049 RP --- 63:262143 01:123456 --:------ 3220 005 004012014D
2020-10-21T09:54:42.878142 072 RQ --- 01:123456 63:262143 --:------ 3220 005 0080130000
2020-10-21T09:54:43.338214 049 RP --- 63:262143 01:123456 --:------ 3220 005 0070130000
2020-10-21T09:54:43.478221 072 RQ --- 01:123456 63:262143 --:------ 3220 005 0080190000
2020-10-21T09:54:43.880402 048 RP --- 63:262143 01:123456 --:------ 3220 005 00401929E6
2020-10-21T09:54:44.078301 072 RQ --- 01:123456 63:262143 --:------ 3220 005 00801A0000
2020-10-21T09:54:44.421372 049 RP --- 63:262143 01:123456 --:------ 3220 005 00C01A2C33
2020-10-21T09:54:44.478364 073 RQ --- 01:123456 63:262143 --:------ 3220 005 00801C0000
2020-10-21T09:54:44.958543 048 RP --- 63:262143 01:123456 --:------ 3220 005 00401C28CC
2020-10-21T09:54:45.078446 072 RQ --- 01:123456 63:262143 --:------ 3220 005 0080730000
2020-10-21T09:54:45.500504 049 RP --- 63:262143 01:123456 --:------ 3220 005 00407300CA

The controller may ask the OTB for others (or other packet verbs are used), I'd say those would be event-driven. In addition, this one is unique in that it is not using a null ID for the OTB device_id (i.e. 63:262143 instead of (say) 10:234567), and I'm yet to work out why that is the case, but other logs are consistent with what I've said so far.

It is noteable to say that outside weather (which may be known to the OT boiler) is likely of no concern to an evohome controller.

From a quick look, it is the following codes exchanged between the controller and the OTB is which is used for obtaining the necessary information to make things work:

2020-03-04T13:33:42.850399 065 RQ --- 01:123456 10:787878 --:------ 3EF0 001 00
2020-03-04T13:33:42.881792 063 RP --- 10:787878 01:123456 --:------ 3EF0 006 0000100000FF

2020-09-12T15:05:31.124771 073 RQ --- 01:123456 10:787878 --:------ 22D9 001 00
2020-09-12T15:05:31.186007 070 RP --- 10:787878 01:123456 --:------ 22D9 003 0003E8

2020-09-12T15:10:28.288084 071  I --- 01:123456 --:------ 10:787878 3150 002 FC45

I have not had enough time to explore the above in full, but decoding it may be insightful:

13:33:42.850 || CTL:123456 | OTB:787878 | RQ | actuator_state   | 00       || {}
13:33:42.881 || OTB:787878 | CTL:123456 | RP | actuator_state   | 00001... || {'actuator_enabled': False, 'modulation_level': 0.0, '_unknown_0': '10', 'flame_active': False, 'flame_state': '00', '_unknown_1': '00FF'}
15:05:31.124 || CTL:123456 | OTB:787878 | RQ | boiler_setpoint  | 00       || {}
15:05:31.186 || OTB:787878 | CTL:123456 | RP | boiler_setpoint  | 0003E8   || {'boiler_setpoint': 10.0}
15:10:28.288 || CTL:123456 | OTB:787878 |  I | heat_demand      | FC45     || {'domain_id': 'FC', 'heat_demand': 0.345}

I do not know if OT faults make it into evohome - if someone is interested, we could set up a test easily enough - PM me (I'd be happy to lend you the necessary HW to eavesdrop this).

What I would really want is a copy of a OTB being bound to a controller - the initial negotiation may be very insightful - PM me for that too, if you'd like.

[StuartP]

I've dropped you a PM as I'm about to replace my TPI boiler interface with OTB.

[oxygen]

Hey there
I've just seen about the new firmware, and the bug you are facing.
I'm still running the old firmware, so I'm a bit "scared" to ask for the new one when I read about your bug.

So if I understand correctly you loss:
- OEM diagnostic code
- Relative modulation level
- OEM fault code
- Flame On
- Return Water Temperature
- DHW Temperature (My setup has the boiler controlling the DHW on its own)
- Boiler Water Temperature
- CH Water Pressure
- Control Setpoint

Is that correct ?
I may ask for the new firmware to confirm your findings, but I was happy with my current readings
(on the side note, I still have an OTGW sitting around that I could fireup to restore my readings)

I've received the update last night it seems.
So far, I'm still collecting all this data from the HGI80.
It may be due to the boiler controller behaving differently on different setups ?

I'm logging back all data fetched by the HGI80, and so far, none has been lost.

[bruce_miranda]

Or it could be that Resideo have fixed the bug that I reported to them. According to them, they were surprised that the controller was no longer requesting this data, they believed that all OT functionality was untouched.

[bruce_miranda]

@oxygen, try this. Remove the battery of the controller for a brief moment and let the controller reboot. Then check if the OT parameters are still being updated on Domoticz every 5 mins.

[oxygen]

As I was going to be away for the holidays, I haven't done the controller reboot yet.
But I have not forgotten about this, and will proceed now asap.

I'll let you know if I indeed loose the OT data then.

[bruce_miranda]

And also would you please report what actual firmware version, you are on now after the reboot.