Intergas (boiler/thermostat) smart power issues

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jvwdev
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Intergas (boiler/thermostat) smart power issues

Post by jvwdev »

Boiler: Intergas Kombi Kompact HRE 28/24 A
Thermostat: Intergas Comfort Touch

I upgraded from a Honeywell Round on/off to a new thermostat which supports OpenTherm.
The thermostat requires smart power support, my boiler also supports this (Intergas boilers that have been built after feb. 2017).

In monitor mode all works fine, as if the OTGW isn't there, but then I'm unable to read any messages.
I've read on the forum here that this is expected. In gateway mode, when I first connect the thermostat and afterwards turn on the boiler, the devices are able to communicate, but eventually the thermostat disconnects.
The thermostat shows an OT error on screen.
When testing I also have seen the thermostat disconnect after requesting the model of the boiler and other times it doesn't fail there.

Code: Select all

23:09:07.633068	OpenTherm Gateway 5.1
23:09:07.641134	Command: SC=23:09/6
23:09:07.649927	Command: SR=21:11,20
23:09:07.655061	Command: SR=22:7,229
23:09:07.660197	Thermostat disconnected
23:09:07.726583	SC: 23:09/6
23:09:07.733888	SR: 21:11/20
23:09:07.743091	SR: 22:7/229
23:09:08.608396	R00000000	Read-Data 	Status (MsgID=0): 00000000 00000000
		   - CH enable: disabled (0)
		   - DHW enable: disabled (0)
		   - Cooling enable: disabled (0)
		   - OTC active: not active (0)
		   - CH2 enable: disabled (0)
		   - Summer/winter mode: winter (0)
		   - DHW blocking: unblocked (0)
23:09:09.619664	R00000000	Read-Data 	Status (MsgID=0): 00000000 00000000
		   - CH enable: disabled (0)
		   - DHW enable: disabled (0)
		   - Cooling enable: disabled (0)
		   - OTC active: not active (0)
		   - CH2 enable: disabled (0)
		   - Summer/winter mode: winter (0)
		   - DHW blocking: unblocked (0)
23:09:10.612690	R00000000	Read-Data 	Status (MsgID=0): 00000000 00000000
		   - CH enable: disabled (0)
		   - DHW enable: disabled (0)
		   - Cooling enable: disabled (0)
		   - OTC active: not active (0)
		   - CH2 enable: disabled (0)
		   - Summer/winter mode: winter (0)
		   - DHW blocking: unblocked (0)
23:09:11.101130	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:11.123229	R100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:11.141457	Thermostat connected
23:09:11.464811	High power
23:09:12.283891	Low power
23:09:12.330353	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:13.135772	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:13.562496	High power
23:09:14.383417	Low power
23:09:14.429737	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:15.235059	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:15.708870	High power
23:09:16.499294	Low power
23:09:16.544702	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:17.335932	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:17.775195	High power
23:09:18.579576	Low power
23:09:18.625965	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:19.432678	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:19.859470	High power
23:09:20.679432	Low power
23:09:20.726534	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:21.533439	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:21.959798	High power
23:09:22.780780	Low power
23:09:22.827573	T100201AD	Write-Data	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:22.985194	BD00201AD	Write-Ack 	Master configuration (MsgID=2): 00000001 173
		   - Smart power: supported (1)
23:09:23.080295	High power
23:09:23.760449	T00030000	Read-Data 	Slave configuration (MsgID=3): 00000000 0
23:09:23.888864	B400341AD	Read-Ack  	Slave configuration (MsgID=3): 01000001 173
		   - DHW: present (1)
		   - Control type: modulating (0)
		   - Cooling: not supported (0)
		   - DHW: instantaneous (0)
		   - Master pump control: allowed (0)
		   - CH2: not present (0)
		   - Remote water filling: not available (1)
		   - Heat/cool mode control: heat (0)
23:09:24.124783	T807F0000	Read-Data 	Slave product version (MsgID=127): 0 0
23:09:24.295400	B707F0000	Unk-DataId	Slave product version (MsgID=127): 0 0
23:09:24.516456	T107E010F	Write-Data	Master product version (MsgID=126): 1 15
23:09:24.689846	B507E0000	Write-Ack 	Master product version (MsgID=126): 0 0
23:09:24.926849	T00000000	Read-Data 	Status (MsgID=0): 00000000 00000000
		   - CH enable: disabled (0)
		   - DHW enable: disabled (0)
		   - Cooling enable: disabled (0)
		   - OTC active: not active (0)
		   - CH2 enable: disabled (0)
		   - Summer/winter mode: winter (0)
		   - DHW blocking: unblocked (0)
23:09:25.019814	BC0000000	Read-Ack  	Status (MsgID=0): 00000000 00000000
		   - Fault indication: no fault (0)
		   - CH mode: not active (0)
		   - DHW mode: not active (0)
		   - Flame status: flame off (0)
		   - Cooling status: not active (0)
		   - CH2 mode: not active (0)
		   - Diagnostic indication: no diagnostics (0)
		   - Electricity production: not active (0)
23:09:25.257746	T00390000	Read-Data 	Max CH water setpoint (MsgID=57): 0.00
23:09:25.401291	BF0390000	Unk-DataId	Max CH water setpoint (MsgID=57): 0.00
23:09:25.410730	AC0395A00	Read-Ack  	Max CH water setpoint (MsgID=57): 90.00
23:09:25.668197	T00110000	Read-Data 	Relative modulation level (MsgID=17): 0.00
23:09:25.794379	BC0110000	Read-Ack  	Relative modulation level (MsgID=17): 0.00
23:09:26.063203	T80640000	Read-Data 	Remote override function (MsgID=100): 00000000
23:09:26.189806	B40640003	Read-Ack  	Remote override function (MsgID=100): 00000011
		   - Manual change priority: enable overrule (1)
		   - Program change priority: enable overrule (1)
23:09:26.214947	A40640000	Read-Ack  	Remote override function (MsgID=100): 00000000
		   - Manual change priority: disable overrule (0)
		   - Program change priority: disable overrule (0)
23:09:26.457798	T90E61500	Write-Data	Message ID 230 (MsgID=230): 5376
23:09:26.598621	B70E60000	Unk-DataId	Message ID 230 (MsgID=230): 0
23:09:26.850734	T90E60901	Write-Data	Message ID 230 (MsgID=230): 2305
23:09:26.992934	B70E60000	Unk-DataId	Message ID 230 (MsgID=230): 0
23:09:27.245336	T90E61E02	Write-Data	Message ID 230 (MsgID=230): 7682
23:09:27.403357	B70E60000	Unk-DataId	Message ID 230 (MsgID=230): 0
23:09:27.656087	T10E60503	Write-Data	Message ID 230 (MsgID=230): 1283
23:09:27.800461	B70E60000	Unk-DataId	Message ID 230 (MsgID=230): 0
23:09:28.050127	T90E61D04	Write-Data	Message ID 230 (MsgID=230): 7428
23:09:28.207726	B70E60000	Unk-DataId	Message ID 230 (MsgID=230): 0
23:09:28.445907	T90E62C05	Write-Data	Message ID 230 (MsgID=230): 11269
23:09:28.603477	B70E60000	Unk-DataId	Message ID 230 (MsgID=230): 0
23:09:28.841042	T00110000	Read-Data 	Relative modulation level (MsgID=17): 0.00
23:09:29.001010	BC0110000	Read-Ack  	Relative modulation level (MsgID=17): 0.00
23:09:29.235133	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:29.409083	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:29.629858	T00000300	Read-Data 	Status (MsgID=0): 00000011 00000000
		   - CH enable: enabled (1)
		   - DHW enable: enabled (1)
		   - Cooling enable: disabled (0)
		   - OTC active: not active (0)
		   - CH2 enable: disabled (0)
		   - Summer/winter mode: winter (0)
		   - DHW blocking: unblocked (0)
23:09:29.804181	BC0000300	Read-Ack  	Status (MsgID=0): 00000011 00000000
		   - Fault indication: no fault (0)
		   - CH mode: not active (0)
		   - DHW mode: not active (0)
		   - Flame status: flame off (0)
		   - Cooling status: not active (0)
		   - CH2 mode: not active (0)
		   - Diagnostic indication: no diagnostics (0)
		   - Electricity production: not active (0)
23:09:30.039190	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:30.211802	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:30.431541	T00390000	Read-Data 	Max CH water setpoint (MsgID=57): 0.00
23:09:30.527054	BF0390000	Unk-DataId	Max CH water setpoint (MsgID=57): 0.00
23:09:30.537050	AC0395A00	Read-Ack  	Max CH water setpoint (MsgID=57): 90.00
23:09:30.780095	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:30.905142	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:31.126521	T90011F03	Write-Data	Control setpoint (MsgID=1): 31.01
23:09:31.221073	B50011F03	Write-Ack 	Control setpoint (MsgID=1): 31.01
23:09:31.473486	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:31.600854	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:31.867995	T10181511	Write-Data	Room temperature (MsgID=24): 21.07
23:09:32.010632	BD0181511	Write-Ack 	Room temperature (MsgID=24): 21.07
23:09:32.262865	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:32.404861	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:32.671954	T900E6400	Write-Data	Maximum relative modulation level (MsgID=14): 100.00
23:09:32.814685	B700E0000	Unk-DataId	Maximum relative modulation level (MsgID=14): 0.00
23:09:33.068626	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:33.209812	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:33.462834	T90101500	Write-Data	Room setpoint (MsgID=16): 21.00
23:09:33.620276	B50101500	Write-Ack 	Room setpoint (MsgID=16): 21.00
23:09:33.860471	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:34.014379	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:34.251777	T80190000	Read-Data 	Boiler water temperature (MsgID=25): 0.00
23:09:34.411229	B40191D1E	Read-Ack  	Boiler water temperature (MsgID=25): 29.12
23:09:34.646084	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:34.819174	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:35.056233	T80640000	Read-Data 	Remote override function (MsgID=100): 00000000
23:09:35.214402	B40640003	Read-Ack  	Remote override function (MsgID=100): 00000011
		   - Manual change priority: enable overrule (1)
		   - Program change priority: enable overrule (1)
23:09:35.246128	A40640000	Read-Ack  	Remote override function (MsgID=100): 00000000
		   - Manual change priority: disable overrule (0)
		   - Program change priority: disable overrule (0)
23:09:35.449316	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:35.609964	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:35.843952	T00000300	Read-Data 	Status (MsgID=0): 00000011 00000000
		   - CH enable: enabled (1)
		   - DHW enable: enabled (1)
		   - Cooling enable: disabled (0)
		   - OTC active: not active (0)
		   - CH2 enable: disabled (0)
		   - Summer/winter mode: winter (0)
		   - DHW blocking: unblocked (0)
23:09:36.017449	BC000030A	Read-Ack  	Status (MsgID=0): 00000011 00001010
		   - Fault indication: no fault (0)
		   - CH mode: active (1)
		   - DHW mode: not active (0)
		   - Flame status: flame on (1)
		   - Cooling status: not active (0)
		   - CH2 mode: not active (0)
		   - Diagnostic indication: no diagnostics (0)
		   - Electricity production: not active (0)
23:09:36.255998	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:36.410873	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:36.648434	T00030000	Read-Data 	Slave configuration (MsgID=3): 00000000 0
23:09:36.822019	B400341AD	Read-Ack  	Slave configuration (MsgID=3): 01000001 173
		   - DHW: present (1)
		   - Control type: modulating (0)
		   - Cooling: not supported (0)
		   - DHW: instantaneous (0)
		   - Master pump control: allowed (0)
		   - CH2: not present (0)
		   - Remote water filling: not available (1)
		   - Heat/cool mode control: heat (0)
23:09:37.090741	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:37.217726	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:37.485301	T90011EE3	Write-Data	Control setpoint (MsgID=1): 30.89
23:09:37.627545	B50011EE3	Write-Ack 	Control setpoint (MsgID=1): 30.89
23:09:37.878928	T00090000	Read-Data 	Remote override room setpoint (MsgID=9): 0.00
23:09:37.890961	SC: 23:09/7
23:09:37.925556	Thermostat disconnected
23:09:38.020470	BC0090000	Read-Ack  	Remote override room setpoint (MsgID=9): 0.00
23:09:38.684831	Error 03
23:09:38.779017	R10010000	Write-Data	Control setpoint (MsgID=1): 0.00
23:09:38.920593	BD0010000	Write-Ack 	Control setpoint (MsgID=1): 0.00
23:09:39.472770	Error 03
23:09:39.854445	R00060000	Read-Data 	Remote parameter flags (MsgID=6): 00000000 00000000
I would like to know what the reason for the disconnect is, the smart power or Intergas not following the OT spec.
Included a couple logs and a diagnostics firmware log.

Thanks in advance!
Attachments
intergas-otgw-logs.zip
(11.55 KiB) Downloaded 126 times
hvxl
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Posts: 1965
Joined: Sat Jun 05, 2010 11:59 am
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Re: Intergas (boiler/thermostat) smart power issues

Post by hvxl »

Thank you for providing logs along with your question. That makes understanding the problem so much easier.

The OTGW concludes that the thermostat is disconnected when it detects a voltage above 2.38V on the analog input from the thermostat. With R5=33k and R6=4k7, that value translates to a voltage above 19.11V on the actual Opentherm line to the thermostat. The maximum voltage within the Opentherm specification is 18V. So anything higher than that is not a valid Opentherm level.

Your diagnostic output shows that the OTGW found a level of 2.32V from your thermostat. That would translate to 18.64V on the Opentherm line. That's already outside the specification. It only has to rise a bit more to exceed the limit applied by the OTGW.

The above calculations assume perfect resistor values. However, the resistors have a tolerance of 10%. In the worst case scenario, R5 could be 10% too low, and R6 10% too high. In that case a line voltage above 16.07V would already result in a voltage above 2.38V on the analog input. A supply voltage below 5V for the PIC would only exacerbate the problem. In practice I have never found resistors that are anywhere near 10% off, though.

To determine if the resistor tolerances are the problem, you could disconnect the thermostat and then measure the voltage on the X1 connector (let's call that V1), PIC pin 17 (V2), and Vcc. Then the following calculation would give the actual line voltage that is considered "open":
  • Vopen = Vcc * 122 / 256 * V1 / V2
For example, on one of my OTGWs, V1=24.36V, V2=3.042V, and Vcc=4.99V. That would produce a Vopen of 19.04V.

I'm not entirely sure anymore if a very low voltage on the thermostat interface would also cause the OTGW to conclude that the thermostat is disconnected. But considering your diagnostic output, as well as the timestamps in your log, that's unlikely to be the scenario here.

After figuring out which device to swear at, you probably want to resolve the problem. This can be done in the firmware by increasing the V_OPEN value. Each unit represents 0.16V on the line. So you can set it to 128 to raise the threshold to 20.05V.

If you're not comfortable changing the code, you can also modify the hardware. As indicated above, to tweak the voltage divider towards a safer outcome, you either have to increase R5, or decrease R6. Decreasing resistance is normally easier to do, because you can just put a high value resistor in parallel.
Schelte
jvwdev
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Posts: 3
Joined: Sun Nov 21, 2021 8:19 pm

Re: Intergas (boiler/thermostat) smart power issues

Post by jvwdev »

Thank you for the detailed explanation.

Measured the required values with the thermostat disconnected:

V1 = 23.20
V2 = 2.904
Vcc = 5.044
Vopen => 19.20

I prefer to modify the software, so I increased V_OPEN to 128.
The problem still appeared, but maybe not as quick as before.

I kept increasing V_OPEN, even tested with 142 but that didn't help either.

With the included log with V_OPEN=142, I didn't modify the thermostat or remotely set any values.
After 3.5 minutes the thermostat disconnects.
Attachments
intergas-otgw-vopen142.zip
(15.63 KiB) Downloaded 122 times
hvxl
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Posts: 1965
Joined: Sat Jun 05, 2010 11:59 am
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Re: Intergas (boiler/thermostat) smart power issues

Post by hvxl »

Assuming the 3.5 minute interval you are referring to is 20:20:32 to 20:24:08, there is a significant difference between your first log and this one: At the point where things stop working, the logs don't show the "Thermostat disconnected" message anymore. So it looks like the V_OPEN change had the expected effect.

But now there is an "OpenTherm Gateway 5.1" message. That is an indication that the OTGW has restarted. The interesting question is, why? You can obtain this information by executing the PR=Q command after this happens.
Schelte
jvwdev
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Posts: 3
Joined: Sun Nov 21, 2021 8:19 pm

Re: Intergas (boiler/thermostat) smart power issues

Post by jvwdev »

You are right, I didn't realize it was a reset.

The disconnect reason is B: Brown out (supply voltage dropped below 4.35V).
I swapped to a different USB charger, this one is 5.2 V
This works perfectly :)

I kept V_OPEN at 128, even though I could probably lower it.
Thank you for the help! I'll make a longer log with startup messages to upload for the equipment matrix.
hvxl
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Posts: 1965
Joined: Sat Jun 05, 2010 11:59 am
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Re: Intergas (boiler/thermostat) smart power issues

Post by hvxl »

Great that the problem is solved.

It's fine to leave V_OPEN at 128. I should probably change it in the source code. The current value is a bit too close for comfort. It was set so tight because at some point the Nodo shop suggested that the OTGW could be powered by a 20V power supply. The power supply they delivered also had a 24V setting, which should really be used. On the newer versions of the OTGW, the 24V is generated from 5V. So there is no reason at all to account for a 20V power supply.
Schelte
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