---
tag: m0191
title: Wait for Chamber Temperature
brief: Wait for the chamber to reach target temperature.
author: shitcreek
contrib: thinkyhead

group: thermal

codes: [ M191 ]

notes:
  - This command (as well as [`M109`](/docs/gcode/M109.html) and [`M190`](/docs/gcode/M190.html)) can block new commands from the host. To break out of wait for temperature using [`M108`](/docs/gcode/M108.html) from the host, enable `EMERGENCY_PARSER`.
  - Use [`M141`](/docs/gcode/M141.html) to set the chamber temperature and proceed without waiting.

parameters:
  -
    tag: S
    optional: true
    description: Target temperature (wait only when heating).
    values:
      -
        tag: temp
        type: float
  -
    tag: R
    optional: true
    description: Target temperature (wait for cooling or heating).
    values:
      -
        tag: temp
        type: float

examples:
  -
    pre: Set target chamber temperature and wait (if heating)
    code: M191 S80
  -
    pre: Set target chamber temperature, wait even if cooling
    code: M191 R40

---

This command optionally sets a new target chamber temperature and waits for the target temperature to be reached before proceeding. If the temperature is set with `S` then it waits *only when heating*.
