Log error on simple template. How to handle unavailable/unknown states?

Configuration
1

First attempt at templating for me/ I’m trying to do a simple value adjustment for a temperature sensor. It works OK except there is always an error in the log when the entity is unavailable (flaky bluetooth connection!)

My template is:

{% if states('sensor.ibs_th_0373_temperature') | is_number %}
	{{ states('sensor.ibs_th_0373_temperature') | float - 3.5 }}
{% else %}
	{{ states('sensor.ibs_th_0373_temperature') }}
{% endif %}

and the log error is
ValueError: Sensor sensor.calibrated_pool_temperature has device class 'temperature', state class 'measurement' unit '°C' and suggested precision 'None' thus indicating it has a numeric value; however, it has the non-numeric value: 'unavailable' (<class 'str'>)

So I’m unclear how to handle the unavailable state. I don’t do any math if the state isn’t a number but apparently that’s not good enough!

I must have missed something obvious in the docs but I can’t find it :thinking:

2

If the temperature sensor’s value is not a number, this version reports the Template sensor’s existing value.

{% if states('sensor.ibs_th_0373_temperature') | is_number %}
	{{ states('sensor.ibs_th_0373_temperature') | float - 3.5 }}
{% else %}
	{{ this.state }}
{% endif %}
3

That would work I guess, but it would still be good to know that the sensor is unavailable.

4

I assume that template is used in a Template Sensor. Are you using its availability option?

5

It is in a template sensor. I created it through the UI (settings > devices&services > helpers)

If it’s not in the UI, I didn’t do it! This is all I did:

Screenshot 2024-07-04 125218
Screenshot 2024-07-04 125218580×779 27.1 KB

I wasn’t aware of the availability option.

If I’m understanding you correctly, I’d need to add another template for Availability? If so, where would I do that? I can’t find the YAML that the UI created.

6

  • You can create a Template Sensor via the UI (referred to as a Template Sensor helper).

  • You can create a Template Sensor via YAML.

A Template Sensor helper only offers a subset of the features available in its more capable YAML-based version.

In order to take advantage of a Template Sensor’s additional features, like availability, you will have to create it in YAML (i.e. replace the Template Sensor helper you currently have).

7

OK. I’ll give that a try. Appreciate the help.

Sucks that the UI gets you so far and then abandons you without even getting the starting YAML. Inconsistent with other parts of the UI.

8

I’m hoping that a Template Sensor helper will eventually support all the features of a Template Sensor. Currently it’s an MVP implementation (minimum viable product).

9

Just a thought:

Keep the Template Sensor helper (with the change I suggested) and create a new one in YAML (it will need a different entity_id).

Observe how they operate when encountering availability issues and choose which you prefer.

10

You could use none when the state of the source sensor is not a number. That is accepted (will not generate errors in your log) and the template sensor will become unknown

{% if states('sensor.ibs_th_0373_temperature') | is_number %}
	{{ states('sensor.ibs_th_0373_temperature') | float - 3.5 }}
{% else %}
	{{ states('sensor.ibs_th_0373_temperature') }}
{% endif %}

Or like this

{% set source = states('sensor.ibs_th_0373_temperature') | float(none) %}
{{ source - 3.5 if source is not none else source }}
11

@TheFes
I’m still learning Jinja so your second example is interesting.

The thing is
{{ states('sensor.ibs_th_0373_temperature') }}

is what craps out in the log. I think because I defined the sensor as a measurement class which is a number whereas {{ states('sensor.yadayada...}} returns a string if the state is unknown. It makes sense but this is my first template sensor so there is a lot to learn :grinning:

This is what I ended up with which works quite well:

template:
    - sensor:
        name: "Pool Temp (Calibrated)"
        unit_of_measurement: "°C"
        state_class: "measurement"
        device_class: "temperature"
        state: >
            {{ states('sensor.ibs_th_0373_temperature') | float - 3.5 }}
        availability: >
            {{ is_number(states('sensor.ibs_th_0373_temperature')) }}

Thanks everyone for the help. I’ve learned a lot!

This seems like a heck of a lot of work to subtract 3.5 from an existing value though?! Is there a simpler way?