diff --git a/CHANGELOG.md b/CHANGELOG.md
index b10c8b97..926ecb00 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,8 @@ will consitute of a breaking change warranting a new major release:
   equal or above v4. However, this software version is compatible to both v3 and v4 of the firmware.
 - The firmware version variables are global statics inititalized early during the program
   runtime now. This makes it possible to check the firmware version earlier.
+- The TCS controller will now always command heaters OFF when being blind for thermal
+  components (no sensors available), irrespective of current switch state.
 
 ## Fixed
 
diff --git a/mission/controller/ThermalController.cpp b/mission/controller/ThermalController.cpp
index 50eb8dfa..a235e707 100644
--- a/mission/controller/ThermalController.cpp
+++ b/mission/controller/ThermalController.cpp
@@ -1599,8 +1599,7 @@ void ThermalController::ctrlComponentTemperature(HeaterContext& htrCtx) {
     // No sensors available, so switch the heater off. We can not perform control tasks if we
     // are blind..
     if (chooseHeater(htrCtx.switchNr, htrCtx.redSwitchNr)) {
-      if (heaterCtrlAllowed() and
-          (heaterHandler.getSwitchState(htrCtx.switchNr) == HeaterHandler::SwitchState::ON)) {
+      if (heaterCtrlAllowed()) {
         heaterSwitchHelper(htrCtx.switchNr, HeaterHandler::SwitchState::OFF, currThermalComponent);
       }
     }
@@ -1683,7 +1682,8 @@ void ThermalController::checkLimitsAndCtrlHeater(HeaterContext& htrCtx) {
     return;
   }
 
-  htrCtx.switchState = heaterHandler.getSwitchState(htrCtx.switchNr);
+  htrCtx.switchState =
+      static_cast<HeaterHandler::SwitchState>(heaterInfo.heaterSwitchState[htrCtx.switchNr]);
   // Heater off
   if (htrCtx.switchState == HeaterHandler::SwitchState::OFF) {
     if (sensorTemp < htrCtx.tempLimit.opLowerLimit and heaterCtrlAllowed()) {
diff --git a/mission/tcs/HeaterHandler.cpp b/mission/tcs/HeaterHandler.cpp
index 8416a7f7..07e6f0eb 100644
--- a/mission/tcs/HeaterHandler.cpp
+++ b/mission/tcs/HeaterHandler.cpp
@@ -419,13 +419,13 @@ ReturnValue_t HeaterHandler::getAllSwitchStates(std::array<SwitchState, 8>& stat
 }
 
 bool HeaterHandler::allSwitchesOff() {
-  bool allSwitchesOrd = false;
   MutexGuard mg(handlerLock, LOCK_TYPE, LOCK_TIMEOUT, LOCK_CTX);
-  /* Or all switches. As soon one switch is on, allSwitchesOrd will be true */
   for (power::Switch_t switchNr = 0; switchNr < heater::NUMBER_OF_SWITCHES; switchNr++) {
-    allSwitchesOrd = allSwitchesOrd || heaterVec.at(switchNr).switchState;
+    if (heaterVec.at(switchNr).switchState == SwitchState::ON) {
+      return false;
+    }
   }
-  return !allSwitchesOrd;
+  return true;
 }
 
 MessageQueueId_t HeaterHandler::getCommandQueue() const { return commandQueue->getId(); }