diff --git a/tcl/drivers/heliox.tcl b/tcl/drivers/heliox.tcl
index 42021b0..3286fa3 100644
--- a/tcl/drivers/heliox.tcl
+++ b/tcl/drivers/heliox.tcl
@@ -104,6 +104,7 @@ proc heliox::check_set {} {
         th setsorb [sct target]
       }
       set mainsensor /th/low
+      tt dblctrl 0
       tt set 1.25
       set state "low-T mode"
     }
@@ -112,6 +113,7 @@ proc heliox::check_set {} {
       th setsorb 40
       th set 0
       th mainloop setsorb
+      tt dblctrl 0
       tt set 1.25
     }
     default {
@@ -170,6 +172,7 @@ proc heliox::check_mode {} {
           th setsorb [expr min(1.8, [hvali /th/target])]
         }
         tt set 1.25
+        tt dblctrl 0
       } else {
         clientput "the 3He pot is probably empty"
         error "condense needed before lowT mode"
@@ -183,6 +186,7 @@ proc heliox::check_mode {} {
       th mainloop set
       th setsorb 40
       tt set 1.25
+      tt dblctrl 0
       set state "-> condense"
       hsetprop /th target 0.25
       hsetprop /ts target 0.25
@@ -244,9 +248,10 @@ proc heliox::read {} {
   }
   if {[hvali [sct]] == 4} {
       if {$ts > 3} {
+        # above 3 K: set deadline
         nv set [hvali [sct parent]/condenseflow] 
         set lasts_until 0
-        sct condense_deadline [expr $now + 36000]  # timeout: should be 3600
+        sct condense_deadline [expr $now + 3600]  # timeout 1 hour
       } elseif {[result th sorb] > 39} {
         nv set [hvali [sct parent]/condenseflow] 
         # 3He vapor pressure: 200 mbar at 2 K, power law
@@ -261,8 +266,18 @@ proc heliox::read {} {
         set lasts_until [expr int($now + $hours * 3600)]
         calc_pot $lasts_until
         sct condense_deadline [silent [expr $now + 3600] sct condense_deadline]
-        if {$now > [sct condense_deadline]} {
-          clientput "condense timeout - cannot fill pot for lasting $target_hours hours"
+        if {$hours > 8} {
+           set dl [expr  $now + ($target_hours - $hours) * 30]
+           set sdl [silent $dl sct soft_deadline]
+           clientput "T-H [expr $target_hours - $hours] $dl $sdl"
+           if {$dl <= $sdl} {
+             sct soft_deadline $dl
+           } elseif {$now > $sdl + 600} {
+             clientput "stop condensing - target_hours is probably too high - expect only [expr round($hours)] h hold time"
+             set target_hours $hours
+           }
+        } elseif {$now > [sct condense_deadline]} {
+          clientput "condense timeout - hold time is probably very low"
           set target_hours $hours
         }
         if {$hours >= $target_hours} {