diff --git a/fhem/FHEM/93_PWMR.pm b/fhem/FHEM/93_PWMR.pm
index 16e58c06c..37742b051 100644
--- a/fhem/FHEM/93_PWMR.pm
+++ b/fhem/FHEM/93_PWMR.pm
@@ -55,7 +55,12 @@
 # 11.02.19 GA add redesign of maxOffTime
 # 21.01.20 GA fix remove default tempRule if only tempRule1 or tempRule2 is defined
 # 28.12.20 GA fix reset maxOffTimeApply to 0 if heating is needed (decision depends on calculation model) 
-
+# 20.01.21 GA fix remove DoTrigger; 
+#                 the below due to hints from phys1
+#             fix prevent parallel InternalTimer calls
+#             fix remove attribute loglevel
+#             fix reading actorState to correct when non default regex is used
+#             add clear PID helper structure when PWM or PWMR object gets disabled
 
 # module for PWM (Pulse Width Modulation) calculation
 # this module defines a room for calculation 
@@ -127,7 +132,7 @@ PWMR_Initialize($)
   $hash->{UndefFn}   = "PWMR_Undef";
   $hash->{AttrFn}    = "PWMR_Attr";
 
-  $hash->{AttrList}  = "disable:1,0 loglevel:0,1,2,3,4,5 ".
+  $hash->{AttrList}  = "disable:1,0 ".
 			"frostProtect:0,1 ".
 			"autoCalcTemp:0,1 ".
 			"desiredTempFrom ".
@@ -294,14 +299,31 @@ PWMR_CalcDesiredTemp($)
       my $offset = ((((int($min/ 5)) +1 ) * 5 ) - $min) * 60;
       #Log3 ($hash, 4, "offset $min -> ".int($min / 5)." $offset ".($offset / 60));
 
+      RemoveInternalTimer($hash, "PWMR_CalcDesiredTemp");
       InternalTimer($n + $offset, "PWMR_CalcDesiredTemp", $hash, 0);
 
     } else {
+      RemoveInternalTimer($hash, "PWMR_CalcDesiredTemp");
       InternalTimer(gettimeofday()+$hash->{INTERVAL}, "PWMR_CalcDesiredTemp", $hash, 0);
       #Log3 ($hash, 4, "interval not 300");
     }
   }
 
+  # as suggested by phys1
+  # If this device or the IODevice have been disabled, the actor state
+  # and the I- and D-Buffer are no longer valid and have to be reset
+  my $iodev = $hash->{IODev};
+  my $IODev_Disabled = (defined($iodev->{NAME})&&IsDevice($iodev->{NAME},"PWM")&&IsDisabled($iodev->{NAME}))? 1:0;
+  if (IsDisabled($name) || $IODev_Disabled) {
+    readingsSingleUpdate ($hash, "actorState", "unknown", 1); # forces PWMR_ReadRoom to read actorState from device when enabled again
+    if ($hash->{c_PID_useit} != 0) {
+      delete ($hash->{helper}{PID_I_previousTemps}) if (defined (($hash->{helper}{PID_I_previousTemps})));
+      delete ($hash->{helper}{PID_D_previousTemps}) if (defined (($hash->{helper}{PID_D_previousTemps})));
+      $hash->{helper}{PID_I_previousTemps} = [] if ($hash->{c_PID_useit} == 1);
+      $hash->{helper}{PID_D_previousTemps} = [];
+    }
+  }
+
   if (defined($hash->{READINGS}{"desired-temp-until"})) {
     if ($hash->{READINGS}{"desired-temp-until"}{VAL} ne "no" ) {
 
@@ -334,8 +356,6 @@ PWMR_CalcDesiredTemp($)
     #$hash->{READINGS}{"desired-tem"}{TIME} = TimeNow();
     #$hash->{READINGS}{"desired-temp"}{VAL} = $hash->{c_tempFrostProtect};
 
-    #push @{$hash->{CHANGED}}, "desired-temp $hash->{c_tempFrostProtect}";
-    #DoTrigger($name, undef);
  
     #$hash->{STATE}     = "FrostProtect";
     readingsSingleUpdate ($hash,  "state", "FrostProtect", 1);
@@ -380,7 +400,6 @@ PWMR_CalcDesiredTemp($)
     readingsSingleUpdate ($hash,  "state", "Manual", 1);
   }
 
-  #DoTrigger($name, undef);
   return undef;
 
 }
@@ -409,7 +428,6 @@ PWMR_Get($@)
     return "unknown get value, valid is status";
   }
   $hash->{LOCAL} = 1;
-  RemoveInternalTimer($hash);
   my $v = PWMR_CalcDesiredTemp($hash);
   delete $hash->{LOCAL};
 
@@ -513,8 +531,6 @@ PWMR_Set($@)
     #$hash->{READINGS}{$cmd}{VAL} = $val;
 
 
-    #push @{$hash->{CHANGED}}, "$cmd: $val";
-    #DoTrigger($hash, undef);
     return undef
   } 
 
@@ -875,6 +891,7 @@ PWMR_Define($$)
   }
 
   if($hash->{INTERVAL}) {
+    RemoveInternalTimer($hash, "PWMR_CalcDesiredTemp");
     InternalTimer(gettimeofday()+10, "PWMR_CalcDesiredTemp", $hash, 0);
   }
   return undef;
@@ -935,14 +952,12 @@ PWMR_SetRoom(@)
     if (!defined($ret)) {    # sucessfull
       Log3 ($room, 2, "PWMR_SetRoom $room->{NAME}: set $room->{actor} $newState");
        
-      #$room->{actorState}                 = $newState;
-
       readingsBulkUpdate ($room,  "actorState", $newState);
       readingsBulkUpdate ($room,  "lastswitch", time());
       readingsEndUpdate($room, 1);
 
-      push @{$room->{CHANGED}}, "actor $newState";
-      DoTrigger($name, undef);
+      #push @{$room->{CHANGED}}, "actor $newState";
+      #DoTrigger($name, undef);
 
     } else {
       Log3 ($room, 2, "PWMR_SetRoom $name: set $room->{actor} $newState failed ($ret)");
@@ -995,29 +1010,23 @@ PWMR_ReadRoom(@)
 
   if (defined($room->{actor}))
   {
+    my $a_regexp_on = $room->{a_regexp_on};
+
     # starting from 26.01.2013 -> try to read act status .. (may also be invalid if struct)
     if ($defs{$room->{actor}}->{TYPE} eq "RBRelais") {
-      $actorV =  $defs{$room->{actor}}->{STATE};
+      #$actorV =  $defs{$room->{actor}}->{STATE};
+      $actorV = ($defs{$room->{actor}}->{STATE} =~ /^$a_regexp_on$/) ? "on" : "off";
       $room->{READINGS}{actorState}{VAL} = $actorV;
     } elsif (defined($defs{$room->{actor}}->{STATE})) {
-      $actorV =  $defs{$room->{actor}}->{STATE};
+      $actorV = ($defs{$room->{actor}}->{STATE} =~ /^$a_regexp_on$/) ? "on" : "off";
       $room->{READINGS}{actorState}{VAL} = $actorV if ($room->{READINGS}{actorState}{VAL} eq "unknown");
     } elsif (defined($defs{$room->{actor}}->{READINGS}{state}{VAL})) {
-      $actorV = $room->{READINGS}{actorState}{VAL};
+      $actorV = ($defs{$room->{actor}}->{STATE} =~ /^$a_regexp_on$/) ? "on" : "off";
       $room->{READINGS}{actorState}{VAL} = $actorV if ($room->{READINGS}{actorState}{VAL} eq "unknown");
     } else {
       #$actorV = $room->{actorState};
       $actorV = $room->{READINGS}{actorState}{VAL};
     } 
-
-    #my $actorVOrg = $actorV;
-    
-    my $a_regexp_on = $room->{a_regexp_on};
-    if ($actorV =~ /^$a_regexp_on$/) {
-      $actorV = "on";
-    } else {
-      $actorV = "off";
-    }
     #Log3 ($room, 2, "$name actorV $actorV org($actorVOrg) regexp($a_regexp_on)");
   }