Page 1 of 1

Outside temperature sensor

Posted: Tue May 23, 2017 10:03 am
by cyril
Hi all!
I'm succefully using otgw and Baxi Main Four 240 F boiler with Honeywell Round Modulation thermostat, but I have some problem with outside temperature sensor. Obviously, my thermostat and boiler does not support MsgID 27, but I can't understand why I can't see outside temperature in OT Monitor? Sersor is working, I can see it using PS=1 serial command.
Thanks for any advice.

Re: Outside temperature sensor

Posted: Thu May 25, 2017 2:15 pm
by hvxl
Correct. If there is no communication mentioning the outside temperature, OTmonitor has no way of learning its value. Why is that surprising?

Re: Outside temperature sensor

Posted: Thu May 25, 2017 3:30 pm
by cyril
OTGW get this parameter directly from sensor and know it. OT Monitor conmunicate with OTGW. It seems strange, why OT Monitor hide it.

Re: Outside temperature sensor

Posted: Thu May 25, 2017 4:30 pm
by cyril
For example, we can get from boiler parameters, not asked by thermostat, using Add Alternatives command, but we can not get parameter from OTGW.

Re: Outside temperature sensor

Posted: Thu May 25, 2017 5:14 pm
by hvxl
The OTGW reports the opentherm communication between the thermostat and boiler to OTmonitor. If the outside temperature is never transmitted in an opentherm message, OTmonitor doesn't have that information. So there is nothing for it to hide.

The purpose of the outside temperature sensor is to be able to provide the temperature to the thermostat for display or use in its control algorithm. If your thermostat doesn't have that functionality then the temperature sensor is useless.

There currently is no mechanism for the OTGW to report information that has no relation to the heating system it is connected to. If you want that kind of information from the OTGW, you will just have to poll for it.

Re: Outside temperature sensor

Posted: Thu May 25, 2017 5:32 pm
by cyril
Ok. It's clear. May be there is the way to simulate this communication, using SR command, for example? Now I'm using OT value by sending PS=1 and PS=0 commands and parsing log. So I can send this value.