Embed number helper in MQTT message for heating control

Configuration
1

Hi,
I am writing some automations to trigger a my hive thermostat to boost the hot water. I have an automation triggered by a button helper and the following MQTT payload works fine:

{
   "system_mode_water":"emergency_heating",
   "temperature_setpoint_hold_duration_water":"30", 
   "temperature_setpoint_hold_water":"1"
}

This behaves as I would expect but rather than hard code the temperature_setpoint_hold_duration_water to 30 I would like to get the value from a number helper I have (input_number.hot_water_boost_time). I don’t appear to be able to get this to work, i’m sure i’m missing something obvious. Here is my full automation:

- id: "1696679145506"
  alias: Boost Hot Water
  description: ""
  trigger:
    - platform: state
      entity_id:
        - input_button.boost_hotwater_button
  condition: []
  action:
    - service: mqtt.publish
      data:
        qos: 0
        retain: false
        topic: zigbee2mqtt/Boiler Control/set
        payload: '{{"system_mode_water":"emergency_heating","temperature_setpoint_hold_duration_water":states("input_number.hot_water_boost_time"),  "temperature_setpoint_hold_water":"1"}}'
  mode: single

Any help would be much appreciated. Thanks!

2 
- id: "1696679145506"
  alias: Boost Hot Water
  description: ""
  trigger:
    - platform: state
      entity_id:
        - input_button.boost_hotwater_button
  condition: []
  action:
    - service: mqtt.publish
      data:
        qos: 0
        retain: false
        topic: zigbee2mqtt/Boiler Control/set
        payload_template: >
          { "system_mode_water": "emergency_heating",
            "temperature_setpoint_hold_duration_water": {{ states("input_number.hot_water_boost_time") }},
            "temperature_setpoint_hold_water": 1 }

NOTE

For the values of a JSON payload, you don’t need to wrap numbers in quotes unless there’s a special reason obliging you to convert them to strings. Therefore I have removed them from the two number values. If your application requires numeric string values, simply add the quotes back.

3

That’s great, thanks very much!

4

You’re welcome!

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