From 05c2f8082683bc4813f16f9c460182666a7966bf Mon Sep 17 00:00:00 2001
From: kAdonis <35379348+kAdonis@users.noreply.github.com>
Date: Sat, 2 Mar 2019 23:29:10 +0100
Subject: [PATCH] Fix bug in wait-for-heatup (#13290)

---
 Marlin/src/module/temperature.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Marlin/src/module/temperature.cpp b/Marlin/src/module/temperature.cpp
index 6f5c8e226..69a8c835f 100644
--- a/Marlin/src/module/temperature.cpp
+++ b/Marlin/src/module/temperature.cpp
@@ -2887,8 +2887,10 @@ void Temperature::isr() {
 
           if (!residency_start_ms) {
             // Start the TEMP_BED_RESIDENCY_TIME timer when we reach target temp for the first time.
-            if (temp_diff < TEMP_BED_WINDOW) residency_start_ms = now;
-            if (first_loop) residency_start_ms += (TEMP_BED_RESIDENCY_TIME) * 1000UL;
+            if (temp_diff < TEMP_BED_WINDOW) {
+              residency_start_ms = now;
+              if (first_loop) residency_start_ms += (TEMP_BED_RESIDENCY_TIME) * 1000UL;
+            }
           }
           else if (temp_diff > TEMP_BED_HYSTERESIS) {
             // Restart the timer whenever the temperature falls outside the hysteresis.