Climate entity and external temperature sensor

Configuration
1

oHello,
I’ve got a Home Assistant installed on a Raspberry PI 3b (more information at the end of this post). Additionally I have a HomeMatic CCU3 connected via the homematic integration. Via the homematic integration I have integrated a climate entity (https://www.homematic-ip.com/en/products/detail/homematic-ip-radiator-thermostat.html). This climate is controlled via Schedy.

In general this setup works so far to control the room temperature. However, I would like to use a separate temperature sensor for the climate entity, as the temperature sensor included in the thermostat is very inaccurate (as it’s directly attached to the radiator).

What options do I have use such a external/separate temperature sensor for my climate entity?

Thanks & best regards
Kejo

System Health

version: core-2021.3.4
installation_type: Home Assistant OS
dev: false
hassio: true
docker: true
virtualenv: false
python_version: 3.8.7
os_name: Linux
os_version: 5.4.83-v7
arch: armv7l
timezone: Europe/Berlin

logged_in: false
can_reach_cert_server: ok
can_reach_cloud_auth: ok
can_reach_cloud: ok

host_os: Home Assistant OS 5.12
update_channel: stable
supervisor_version: supervisor-2021.03.6
docker_version: 19.03.13
disk_total: 58.0 GB
disk_used: 5.9 GB
healthy: true
supported: true
board: rpi3
supervisor_api: ok
version_api: ok
installed_addons: deCONZ (6.7.2), File editor (5.2.0), Samba share (9.3.0), Node-RED (8.2.0), AppDaemon 4 (0.5.0), Terminal & SSH (9.1.0)

dashboards: 2
resources: 0
views: 2
mode: storage

2

What is your question exactly? Advice on hardware temperature sensors? Or something else?

3

Hi there… to use an external temperature sensor you can use the generic thermostat integration, here you can specify which entity should be the target sensor. Please check out this.


The documentations are details but if you need any more help,.please do post.
4

Thanks for the quick replies so far.
My question is, how do I configure the usage of such a temperature sensor (instead of the integrated one in the thermostat). The temperature sensor entity is already available in Home Assistant.

The Generic Thermostat I have seen as well, but I understood that this is ment to be used with a heater (which can just be switched on/off) and not with a climate entity. So the Generic Thermostat is an actual thermostat which controls the algorithms for getting the desred temperatures. But in my case I have already a real thermostate attached to the radiator and I just want to use another temperature sensor.

Any ideas how to do that?

5

Set your homeatic for the absolute minimum temp in the house. This will be a fall back set point should HA crash.

Then just set an automation with numeric state trigger of whatever sensor you want to use. Use climate.set_temperature to set a temp that will always be higher than the reading on the actual thermostat.

Use an above / below template to change the set point based on the other sensor. This will make the thermostat work like an on off switch.

Use the simple thermostat card in HACS. Set option to hide temperature and follow how to add additional sensors. The first sensor you add will be displayed as the main temp.

Edit:

You could create two scripts to set the high/low set point. Then create an input boolean toggle. Use that in an automation to call the on/off scripts. Now you have an on/off switch for the thermostat.

1 Like
6

any idea??

7

I’m interested in this as well. During the day, I’d like to use the upstairs temperature, and at night I’d like to use the temp reported by the thermostat.

8

Try: https://better-thermostat.org/
There you can use an external temperature sensor, but I havent tried it yet.