hvac_action does not change to idle in some cases

[thomas2403]

I have set up a SmartThermostat for a room. Everything looks fine when it is heating.
But when the current temperature is above the setpoint (desired temperature), the hvac_action stays at heating status and the control_output is at 5%. It never goes below 5% unless I do a restart.
The example below show current_temperature: 23.5°C and temperature: 22°C with pid_i: 0. I would expect, that the output would go to 0%. But it stays at 5%. I want to switch off the gas boiler, when each thermostat is at idle state.

BTW, if someone is wondering. I use an mqtt device, which gives me room temperature and the setpoint for a room. It will only work in 0.5°C steps, but this is OK for me.

Actual status:

min_temp: 7
max_temp: 30
target_temp_step: 0.5
current_temperature: 23.5
temperature: 22
hvac_action: heating
away_temp: null
eco_temp: null
boost_temp: null
comfort_temp: null
home_temp: null
sleep_temp: null
activity_temp: null
control_output: 5
kp: 20
ki: 0.002
kd: 0
ke: 0
pid_mode: auto
pid_i: 0
friendly_name: Thermostat DG Monika
supported_features: 385

Config:

- platform: smart_thermostat
name: Thermostat DG Monika
unique_id: "smart_thermostat_dg_mo"
heater:
- number.e2m_dg_monika_nord_config_valve_position
- number.e2m_dg_monika_sued_config_valve_position
target_sensor: sensor.raumtemperatur_dg_mo
min_temp: 7
max_temp: 30
ac_mode: False
target_temp: 21
keep_alive:
seconds: 60
kp: 20
ki: 0.002
kd: 0
ke: 0
output_min: 0
output_max: 100
pwm: 0
sampling_period: 60
target_temp_step: 0.5
hot_tolerance: 0.0
cold_tolerance: 0.0

Any idea, why this happens?

[ScratMan]

Please add debug: true to your configuration file and restart before checking the pid_p, pid_d and pid_e attributes.
You may also look in the logs to see if an error occurs.

[thomas2403]

Here is the situation again, this time with debug output. I still don't get it, why the output is not going to zero

min_temp: 7
max_temp: 30
target_temp_step: 0.5
current_temperature: 24.5
temperature: 22.5
hvac_action: heating
away_temp: null
eco_temp: null
boost_temp: null
comfort_temp: null
home_temp: null
sleep_temp: null
activity_temp: null
control_output: 5
kp: 20
ki: 0.002
kd: 0
ke: 0
pid_mode: auto
pid_i: 0
pid_p: -40
pid_d: -0.0
pid_e: 0
pid_dt: 60.00013613700867
friendly_name: Thermostat DG Bad
supported_features: 385

[ScratMan]

All pid_... are at 0, control_output being the sum, it shouldn't be non-null. Please look in the logs, there may be an exception raised by home assistant, preventing the PID output value to be stored and applied correctly in the thermostat.