diff --git a/tcl/drivers/sensirion.tcl b/tcl/drivers/sensirion.tcl
index c33f999..cd86083 100644
--- a/tcl/drivers/sensirion.tcl
+++ b/tcl/drivers/sensirion.tcl
@@ -32,9 +32,8 @@ proc stdConfig::sensirion {} {
       prop writecmd "str7 n%-6d int 10 / str9"
 
       node offset wr
-      prop check sensirion::checkCalib
       prop read stdSct::read
-      prop complete sensirion::update
+      prop complete sensirion::update_and_check
       prop update sensirion::update
       prop write stdSct::write
       prop readcmd "str1 o int 10 / str9"
@@ -42,15 +41,15 @@ proc stdConfig::sensirion {} {
 
       node scale wr
       prop read stdSct::read
-      prop complete sensirion::update
-      prop update sensirion::update
-      prop check sensirion::checkCalib
+      prop complete sensirion::update_and_check
+      prop update sensirion::updateScale
       prop write stdSct::write
       prop readcmd "str1 g int 10 / str9"
       prop writecmd "str7 g%-6.4f int 10 / str9"
 
-      node save out
+      node save wr
       prop enum 1
+      prop read sensirion::readSave
       prop write sensirion::saveCalib
       prop help "unchecked: current calib is not saved. set checked: save calib"
 
@@ -75,14 +74,6 @@ proc sensirion::currentCalib {} {
   return [format {%.4f %.4f} [hval [sct objectPath]/offset] [hval [sct objectPath]/scale]]
 }
 
-proc sensirion::checkCalib {} {
-  if {[silent "" currentCalib] ne "[silent 0 sct saved]"} {
-    hupdate [sct parent]/save 0
-  } else {
-    hupdate [sct parent]/save 0
-  }
-}
-
 proc sensirion::saveCalib {} {
   if {[sct target]} {
     sct send "str1 s int 10 / str1"
@@ -99,3 +90,31 @@ proc sensirion::update {} {
   sct update [sct result]
   return idle
 }
+
+proc sensirion::update_and_check {} {
+  sct update [sct result]
+  [sct controller] queue [sct parent]/save progress read
+  return idle
+}
+
+proc sensirion::readSave {} {
+  set current [silent "" currentCalib]
+  set saved [silent "" sct saved]
+  if {$current eq $saved} {
+    sct update 1
+  } else {
+    sct update 0
+  }
+  return idle
+}
+
+proc sensirion::updateScale {} {
+  if {[sct result] == 1 && [silent 0 sct target] != 1} {
+     # probably an uncalibrated sensor was replaced and not initialized
+     sct target 2.3
+     clientput "change nvflow scale from 1 to 2.3"
+     return write
+  }
+  sct update [sct result]
+  return idle
+}