From cf447a54428345903fe9f4c9497a4f32dfa72b08 Mon Sep 17 00:00:00 2001
From: gjdodd <31553294+gjdodd@users.noreply.github.com>
Date: Mon, 24 May 2021 07:54:10 +0100
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9B=20Fix=20flowmeter=20calculation=20?=
 =?UTF-8?q?(#21959)?=
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---
 Marlin/src/feature/cooler.h | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/Marlin/src/feature/cooler.h b/Marlin/src/feature/cooler.h
index 1e24c729f3..9bd98d0b10 100644
--- a/Marlin/src/feature/cooler.h
+++ b/Marlin/src/feature/cooler.h
@@ -78,10 +78,8 @@ public:
 
     // Get the total flow (in liters per minute) since the last reading
     static void calc_flowrate() {
-      //flowmeter_interrupt_disable();
-      //  const uint16_t pulses = flowpulses;
-      //flowmeter_interrupt_enable();
-      flowrate = flowpulses * 60.0f * (1000.0f / (FLOWMETER_INTERVAL)) * (1000.0f / (FLOWMETER_PPL));
+      // flowrate = (litres) * (seconds) = litres per minute
+      flowrate = (flowpulses / (float)FLOWMETER_PPL) * ((1000.0f / (float)FLOWMETER_INTERVAL) * 60.0f);
       flowpulses = 0;
     }