FHTb 80 Homematic MQTT Thermostat control

Hi together,

I want to move my Home control from Openhab to Homeassitant. Important is to get my old FS20 / FHTb 80 equipment to run.

I finally managed it to get made my FS20 Switches being controlled, now I get stuck with my FHTb 80 Thermostat controls.

Setup:
HA on Raspi
Raspberrymatic with CCU-jack installed

Reading values and states works, I can turn switches on/off by MQTT commands.

Using the climate card control I don’t get it how to send my new target temperature ( in this case 21°) to the FHT device.

What do I have to add to my MQTT configuration?

climate:
- name: “Bad Thermostat”
min_temp: 12
max_temp: 30
temp_step: 1
modes:
current_temperature_topic: “device/status/CUX0800001/1/TEMPERATURE”
current_temperature_template: “{{ value_json.v }}”
temperature_command_topic: “device/status/CUX0800001/2/SETPOINT”

For information my working config for FS20 switch:

switch:
- unique_id: FF_Leselampe
name: “Leselampe”
state_topic: “device/status/CUX0200001/1/STATE”
command_topic: “device/set/CUX0200001/1/STATE”
value_template: “{{ value_json.v}}”
payload_on: ‘{“v”:true}’
payload_off: ‘{“v”:false}’
state_on: true
state_off: false
optimistic: false
qos: 0
retain: true

Thank you for any help!!

Frank

This topic might help you: MQTT climate control available?

Thank you. Unfortunately it does not. I read this and so many other articles, I’m honestly totally lost.

Do I have to use an action statement? What has to put into payload to feed the temperature common topic with the desired temperature set by turning the wheel in the climate card?

Looking at the HVAC configuration I’m not able to pick what is necessary due to my lack of MQTT experience :no_good_man:

I found out that changing the target temperature the value is send as a pure number to the MQTT device:

SETPOINT = 27.0

It has to look like this:

SETPOINT = {“v:” 27,0}

I was able to set this format with payload for the switches with

payload_on: ‘{“v”:true}’

Don’t find anything similar for the temperature value.

After hours digging I finally found the error.

The MQTT temperature_command_topic has to be a SET device instead a STATUS device. Life could be so easy…

Working basic configuration:

climate:
- name: “Bad Thermostat”
min_temp: 12
max_temp: 30
temp_step: .5
modes:
current_temperature_topic: “device/status/CUX0800001/1/TEMPERATURE”
current_temperature_template: “{{ value_json.v }}”
temperature_command_topic: “device/set/CUX0800001/2/SETPOINT”

Maybe it’ll help somebody else.

CU
Frank

1 Like

ah good! I wasn’t able to help you, cause I don’t own a FHT 80b, but nice that you have found the cause.

Thanks, this helped me.
Did you manage to show also low battery of FHT and/or valve?

Ok, i found out by myself :wink:
I used binary sensor.

binary_sensor:
- device_class: battery
  name: Bad Thermostat
  payload_on: true
  payload_off: false
  state_topic: "ccu/device/status/CUX0800003/0/LOWBAT"
  value_template: "{{ value_json['v'] }}"