Index: firmware/App/Modes/ModeGenIdle.c
===================================================================
diff -u -ra1452dc7f16d37db53930c3d73992098709d7915 -r54e58f64179ea382d2e2c403c8c3b9a15a612636
--- firmware/App/Modes/ModeGenIdle.c	(.../ModeGenIdle.c)	(revision a1452dc7f16d37db53930c3d73992098709d7915)
+++ firmware/App/Modes/ModeGenIdle.c	(.../ModeGenIdle.c)	(revision 54e58f64179ea382d2e2c403c8c3b9a15a612636)
@@ -109,7 +109,9 @@
     // because the initial guess in the heaters driver needs the target flow to calculate
     // the new PWMs for the main and small primary heaters
     setROPumpTargetFlowRate( TARGET_FLUSH_LINES_RO_FLOW_RATE_L, TARGET_RO_PRESSURE_PSI );
-    startPrimaryHeater();
+
+    setHeaterTargetTemperature( DG_PRIMARY_HEATER, 39.0 );
+    startHeater( DG_PRIMARY_HEATER );
 }
 
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