diff --git a/pid/fancontroller.cpp b/pid/fancontroller.cpp
index 7d4a92d..44852a0 100644
--- a/pid/fancontroller.cpp
+++ b/pid/fancontroller.cpp
@@ -46,15 +46,17 @@
 
 double FanController::inputProc(void)
 {
-    double value = 0;
-    std::vector<int64_t> values;
-    std::vector<int64_t>::iterator result;
+    double value = 0.0;
+    std::vector<double> values;
+    std::vector<double>::iterator result;
 
     try
     {
         for (const auto& name : _inputs)
         {
-            value = _owner->getCachedValue(name);
+            // Read the unscaled value, to correctly recover the RPM
+            value = _owner->getCachedValues(name).unscaled;
+
             /* If we have a fan we can't read, its value will be 0 for at least
              * some boards, while others... the fan will drop off dbus (if
              * that's how it's being read and in that case its value will never
@@ -67,7 +69,7 @@
             {
                 continue;
             }
-            if (value <= 0)
+            if (value <= 0.0)
             {
                 continue;
             }
@@ -82,7 +84,7 @@
     }
 
     /* Reset the value from the above loop. */
-    value = 0;
+    value = 0.0;
     if (values.size() > 0)
     {
         /* the fan PID algorithm was unstable with average, and seemed to work
@@ -166,7 +168,7 @@
     }
 
     // value and kFanFailSafeDutyCycle are 10 for 10% so let's fix that.
-    percent /= 100;
+    percent /= 100.0;
 
     // PidSensorMap for writing.
     for (const auto& it : _inputs)
diff --git a/pid/zone.cpp b/pid/zone.cpp
index 69464e1..e9aaafc 100644
--- a/pid/zone.cpp
+++ b/pid/zone.cpp
@@ -493,12 +493,10 @@
 
 void DbusPidZone::initializeCache(void)
 {
-    auto nan = std::numeric_limits<double>::quiet_NaN();
-
     for (const auto& f : _fanInputs)
     {
-        _cachedValuesByName[f] = {nan, nan};
-        _cachedFanOutputs[f] = {nan, nan};
+        _cachedValuesByName[f] = {0, 0};
+        _cachedFanOutputs[f] = {0, 0};
 
         // Start all fans in fail-safe mode.
         _failSafeSensors.insert(f);
@@ -506,7 +504,7 @@
 
     for (const auto& t : _thermalInputs)
     {
-        _cachedValuesByName[t] = {nan, nan};
+        _cachedValuesByName[t] = {0, 0};
 
         // Start all sensors in fail-safe mode.
         _failSafeSensors.insert(t);
diff --git a/test/zone_mock.hpp b/test/zone_mock.hpp
index b63408f..ba167f4 100644
--- a/test/zone_mock.hpp
+++ b/test/zone_mock.hpp
@@ -18,7 +18,14 @@
     MOCK_METHOD0(updateSensors, void());
     MOCK_METHOD0(initializeCache, void());
     MOCK_METHOD1(getCachedValue, double(const std::string&));
-    MOCK_METHOD1(getCachedValues, ValueCacheEntry(const std::string&));
+
+    // Compatibility interface for getCachedValues
+    ValueCacheEntry getCachedValues(const std::string& s)
+    {
+        auto v = getCachedValue(s);
+        return ValueCacheEntry(v, v);
+    }
+
     MOCK_CONST_METHOD0(getRedundantWrite, bool(void));
     MOCK_METHOD2(addSetPoint, void(double, const std::string&));
     MOCK_METHOD2(setOutputCache,