Comparing sensor values

Configuration
1

Home Assistant
0.49.0

Hi all - I hope someone can point me in the right direction, I’m struggling to find a solution to subtracting one sensor value from another.

My project is to use google calendar to set up a schedule for my heating, and then based on the difference between the desired temp in the schedule and the measured temp from a generic thermostat, the heating can be switched on or off.

In configuration.yaml:

My Generic thermostat looks like this

  • platform: generic_thermostat
    climate.set_operation_mode: auto
    name: “House Temperature”
    heater: switch.heating
    target_sensor: sensor.allan_office_temp
    min_temp: 18
    max_temp: 25
    target_temp: 19
    tolerance: 0.2
    min_cycle_duration:
    seconds: 10
    keep_alive:
    minutes: 3

note: I have also converted this to a float as follows:

  • platform: template
    sensors:
    room_temp_as_float:
    value_template: ‘{{states.climate.house_temperature.attributes.current_temperature | float}}’

My second sensor is from google calendar, and is also converted to a float as follows

  • platform: template
    sensors:
    calendar_as_float:
    value_template: ‘{{states.calendar.heating.attributes.message | float }}’

UP TO THIS POINT, all works perfectly as expected, I can see all the relevant values in Developer Tools <> Sates.

My problem comes when I try to work out the difference between the 2 values (states. calendar_as_float) and (states.room_temp_as_float)

All I seem to get in Developer Tools <> Sates is ‘Unknown’ when I try to subtract one from the other, or if I try an automation, the automation never triggers (I guess that’s because the value_template doesn’t seem to work)

I don’t know if this is relevant or not, but I also have the following errors in Developer Tools / Info:

2017-10-23 09:32:46 WARNING (Thread-8) [netdisco.ssdp] Found malformed XML at http://192.168.0.68:49153/description0.xml:
2017-10-23 09:32:46 WARNING (Thread-8) [netdisco.ssdp] Found malformed XML at http://192.168.0.68:49153/description1.xml:
2017-10-23 09:32:46 WARNING (Thread-8) [netdisco.ssdp] Found malformed XML at http://192.168.0.68:49153/description2.xml:
2017-10-23 09:32:46 WARNING (Thread-8) [netdisco.ssdp] Found malformed XML at http://192.168.0.68:49153/description3.xml:
2017-10-23 09:32:49 WARNING (Thread-8) [netdisco.ssdp] Found malformed XML at http://192.168.0.69:49153/description0.xml:
2017-10-23 09:32:49 WARNING (Thread-8) [netdisco.ssdp] Found malformed XML at http://192.168.0.69:49153/description1.xml:

Thanks in advance

2

Please use code blocks and syntax highlighting.

The log says “Found malformed XML” on several files. In order to help we need to see those files…

3

Hi
Apologies for the delay in replying - I have spent some time upgrading HA to the latest version to see if anything changed - no

I checked my intranet and the IP addresses listed in the malformed XML messages relate to the Sky and SkyQ box that we recently had installed. I have no coding or scripting relating to these devices in my HA configuration.

I think they may be safely disregarded in the context of my enquiry.

Cheers

Allan

4

I also get this error for my Sky Box. I have always disregarded it.